Oudolf Garden Detroit Visit During PPA

I’ve spent the past week in Michigan attending the 2026 Perennial Plant Symposium, and it has been wonderful learning about plants, finding inspiration, and celebrating friendship amongst plantspeople. The educational sessions were top-notch with speakers focusing on ecological design, principles of planting, climate change, and resilient planting.

One of the tour highlights was seeing the plantings at Oudolf Garden Detroit, and I actually remembered my camera this time! It was in its summer splendor thanks in part to head horticulturist Richard Thomas and his team of volunteers but also to the creativity and insight from master plantsman Piet Oudolf.

My previous visit was in June last year, and coming later this summer provided a glimpse of what the garden looks like as the season progresses. And, this time over 100 horticulturists descended on the garden, so it was an interesting dynamic to walk around and discuss aspects of the garden anywhere you went.

I took plenty of photos to document what I saw, and I wanted to share with you readers a few inspiring ideas that I gleaned from the garden.

OUDOLF GARDEN DESIGN

Oudolf Garden Detroit was designed with repeating slightly curving perennial beds with turf on both sides to add legibility and allow for exploration. Paths transected the beds and punctuated it on the north and south ends.

One thing I love about Oudolf designs is the long views. From this perspective it appears there is one long collection of plants instead of the repeating bed–turf–bed-turf arrangement.

Here is another one of these long views across the garden where the plantings seem to meld together. I love the backlighting with the seedheads.

I noticed some mulch around plants. Often this style of planting is touted as mulch-free, so I asked Richard why they used it. He said he uses it strategically during the year to cover bare spots or to reduce the amount of reseeding that happens.

BLOCK, MATRIX, AND ORGANIC BLOCK STYLES

One aspect of naturalistic planting that I know confuses gardeners is plant arrangement styles. There’s matrix and block, but these terms leave people wondering what they mean. Block planting is where plants are grouped together for massed effect. Blocks are often planted to provide some dynamic combination with nearby neighbors featuring color, texture, form, or other aesthetics.

Oudolf Garden Detroit provides some great examples of both styles of arranging plants in naturalistic design. This garden actually featured three different types of planting arrangement beds—block (A), matrix (B), and organic block (C). The letters correspond to these diagrams that were provided on the website. On the drawings the block beds appeared a bit more square on the design than the organic blocks, and the former looked like a quilt pattern while the organic block was more fluid and rounded. Honestly, I couldn’t tell much difference between the regular and organic blocks looking at them on the ground, and the distinction may matter more on paper than in situ.

The matrix beds featured a dominant ground cover layer from which other species emerged. This style focuses on planting design that mimics the layers that one sees in the wild, and it capitalizes on repeating plants across the bed for coherence. These beds primarily used Sporobolus heterolepis (prairie dropseed) as the matrix species.

Some beds featured perennials arranged in strong blocks. Here you can see the delineations between (clockwise from top) Phlox paniculata ‘Sweet Laura’ (garden phlox), Pycnanthemum muticum (clustered mountain mint), 2026 Perennial Plant of the Year Vernonia 'Summer Swan Song' (ironweed), and Amsonia hubrichtii (threadleaf bluestar).

Block planting thrives on creating pairings of plants that have interesting colors, textures, or forms. In the foreground, Calamintha nepeta ssp. nepeta (lesser calamint), Monarda bradburiana (eastern beebalm), and Amsonia hubrichtii (threadleaf bluestar) are blocked, and in the background, Liatris pycnostachya (prairie blazing star) emerges amongst blocks of foliage.

In some spaces, blocks of species like Pycnanthemum muticum had a bold presence because of the sheer size of the colony.

But, in other spaces the blocks mingled more. Pycnanthemum muticum is a bit more broken up with Scutellaria incana (hoary skullcap) and Echinops bannaticus 'Star Frost' (globe thistle).

Here’s an example of plants in the organic block style where they are more curved in their design on paper, but in person I couldn’t tell much difference between these and the regular blocks. Clockwise from the top left: Schizachyrium scoparium 'Blue Paradise' (little bluestem), Allium lusitanicum 'Summer Beauty' (ornamental onion), Molinia caerulea 'Whirlwind' (purple moor grass), and Symphyotrichum oblongifolium 'October Skies' (aromatic aster).

The matrix style of planting was different from the block approach. In these spaces a lower layer of Sporobolus heterolepis (prairie dropseed) covered the ground while species like Echinacea purpurea ‘Virgin’ (purple coneflower) emerged as punctuation marks.

Here you can still see the Sporobolus matrix layer, but notice how there are other larger plants emerging from it. Single plants of Baptisia (wild indigo) can make a statement, or you can have a block of Pycnanthemum muticum amongst the matrix.

PLANT COMBOS

I’m always struck by Piet Oudolf’s ability to create engaging combinations of plants in his designs. He really has an eye for pairing plants, and the following are a few of my favorites to help you think through creating your own combinations.

Sometimes flower forms are repeated like you see here with the orbs on Eryngium yuccifolium (rattlesnake master) and Echinops bannaticus ‘Star Frost’.

We can also repeat color. In this space the repetition of a hint of gray and lavender was a strong combining element among Limonium latifolium (sea lavender), Liatris pycnostachya (prairie blazing star), Echinops bannaticus 'Star Frost', and Pycnanthemum muticum.

I loved this color echo on varied textures from Amorpha canescens (leadplant) and Schizachyrium scoparium 'Blue Paradise'.

Sometimes color echoes can be subtle like how the seed head color of Molinia arundinacea 'Crystal Veil' (tall purple moor grass) matches the purple of Liatris pycnostachya.

One strategy when creating naturalistic plantings is to put two species next to each other that have strong textural contrasts. The button seed heads of Monarda bradburiana contrast nicely with the fine foliage of Amsonia hubrichtii.

Sporobolus heterolepis as a ground cover layer provides a good foil for other plants to emerge from like these blackened seedheads on Baptisia.

I thought this pairing was clever. Stokesia laevis ‘Peachie’s Pick’ was used as a low, colorful ground cover under Asclepias incarnata (swamp milkweed). Even if the Stokesia wasn’t in bloom, it would still provide a good base.

The fading seedheads of Echinacea pallida (pale purple coneflower) provided a flower form contrast with the spires of Veronicastrum virginicum 'Challenger' (Culver's root).

Scattered in the matrix beds were Allium carinatum var. pulchellum (keeled garlic). They provided little fireworks of color.

EAST BED

On the east side of the garden was a triangular bed that featured a matrix of sedges with a few prominent tree, shrub, and perennial species mixed in. Overall, this space was much quieter than the rest of the garden, and it really was a study on the use of greens in the landscape showing us that plants don’t have to be in bloom to be interesting in this style of planting.

Rhus copallinum (shining sumac) was a shrub that was repeated throughout this space, and the shiny leaves contrasted with the finer foliage of the sedges.

Spires of Digitalis parviflora (small-flowered foxglove) and the bold foliage of Heuchera villosa (hairy alumroot) pop against the finer sedge species.

In this shady spot, you can see more diversity of species in the sedge matrix. Of note are the large leaves of Darmera peltata (umbrella plant). The browning leaves are a reminder that even in the north some plants can show sunburn later in the season.

NATIVE MEADOWS

One of the most interesting parts of Oudolf Garden Detroit was the native meadows that were planted to the south of the garden around the Nancy Brown Peace Carillon (header image), or as our daughter Magnolia called it, Rapunzel’s tower. This space is a wetland habitat, and the team has worked to enrich the lowland with diversity. A boardwalk allowed visitors to walk out and explore the area from a slightly elevated height.

From this perspective you can really see the difference between the wilder wetland areas below and the designed gardens in the elevated section above. I think this juxtaposition is helpful because what people think of as “natural” varies, and it really shows you two styles on the gradient.

Hibiscus moscheutos (swamp rose mallow) and Asclepias incarnata (swamp milkweed) thrived in the soils of the native meadows and provided a nice color echo. We saw some monarchs flitting around, too!

I don’t see Verbena hastata (blue vervain) used enough in gardens. The upright habit of this native plant really helps to punctuate plantings.

At the end of the boardwalk was a section of planting that was more flower-rich. It helped to transition the wilder parts of the native meadows back to more managed space.

RAIN GARDENS AND BIRD BORDER

Near the Oudolf Garden Detroit parking lot was a rain garden that helps to capture runoff and provide habitat for birds. Like the east bed, this space was quieter in color and mostly green with a few flowers here and there.

Many rain gardens are more herbaceous in nature, but this one featured a few trees and several shrubs.

Some of my favorite plants to see (or perhaps I should say smell!) in the rain garden were these Clethra alnifolia (summersweet). With the good breeze we had, their fragrance would drift through the air.

And as we were being hurried back on the bus, we had to stop and admire these lovely sedges in the bird border. We assume they are Carex bromoides (brome-like sedge), and this photo shows how effective they can be used amongst other perennials and shrubs.

Thanks for joining me vicariously for my visit to Oudolf Garden Detroit. I hope this post provided you with some ideas, inspiration, and insights into your naturalistic plantings.

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KEEP GROWING

How Nature Places Woodies and What It Teaches Us About Design

My bootcamp session Woodies in Naturalistic Design on May 18 at 6 pm CDT is great for learning how to use trees and shrubs in naturalistic plantings. This session gives you a practical framework for reading your site for trees and shrubs, understanding woody plant behavior, and placing shrubs and trees so your garden builds structure, shines through seasons, and works ecologically from the ground up.

Think for a moment about the last tree or shrub you planted. How did you pick it? Where did you decide to site it? Did you consider how to plant it to seamlessly integrate it into your garden? Or, does it feel like it’s sticking out like a sore thumb?

Placing woodies in plantings can be a source of frustration for designers. Many of us choose plants based on visiting garden centers, inspiration we saw online, or from looking through plant lists. These unfocused decisions can lead to a garden that feels more like a plant collection than something that appeared to happen naturally. And, when we work with woodies that may be around for decades or even centuries to come, thoughtful decisions matter.

To assist us, we can turn to nature for inspiration. We can think about designing with woodies in naturalistic plantings from the perspective of how nature places plants both in the wild and human-altered landscapes.

PLANT COMMUNITY ARCHETYPES

When we look at nature, woody plants arrange themselves into typical patterns based on a variety of factors like water availability, light levels, soil, and competition.

In Planting in a Post-wild World, Thomas Rainer and Claudia West talked about simplifying landscape design by discussing plant community archetypes. They stated, “Focusing on each [plant community] individually could take a lifetime, and more important, distract rather than clarify our task. After all, a montane oak-hickory forest of Virginia may be meaningless to someone in southern England, but a forest is a concept that both will understand. In order to create plantings with emotional resonance, we must first start with a point of reference that has broad appeal.”

They distilled plantings down into a few simple categories. They listed forest, woodland/shrubland, grassland, and edge, and below I’ve teased those out a bit. I also added hedgerows and fencerows as they are prevalent plant communities that exist due to human disturbance.

FOREST

Forests are where woodies grow to the max. Dense foliage cover from the layers of trees above prevent much from growing underneath save for patchy shrubs, ephemeral forbs, and shade-tolerant perennials. Shade levels vary based on the species present and influence what can grow below. For example, deciduous trees will provide light to hit the floor during the winter and early spring for ephemerals; however, evergreens rarely allow light to penetrate, thus limiting what can grow below.

Naturalistic plantings in dense forests often focus on enhancing the plantings at ground plane with stress-tolerant perennials and self sowers. Shrubs can grow in this space, but they may struggle from the lack of light. Also, visual sight lines are important in such a space as having too many shrubs or other plants break the view and can make one feel claustrophobic.

At Porter’s Creek Trail, notice how the ground cover layer is Phacelia fimbriata (fringed phacelia). You can see into the distance without shrubs or other vegetation blocking your view.

At Skylands, moss, ferns, and lichen dominate the layer under the forest.

WOODLANDS

Woodlands tend to be more open where trees are sparsely arranged. The open space is enough for allowing other grasses and shrubs to get established. I have visited glades and pine barrens from North Carolina to Tennessee and admired the diversity of plant species in these varied landscapes.

With a woodland approach, there are opportunities for the woody plants to shine as anchor species. Shrubs and larger perennials can be in orbit around them and grade to shorter grassland habitat.

A barren in east Texas offers a glimpse at a woodland in the wild.

The dark plate in the Lurie Garden features increasing numbers of trees to create the appearance of a woodland.

SHRUBLANDS

Shrublands are where we see shrubs dominate. These spaces may be in transition toward a woodland or forest, or they could also be stable successional states where management strategies or their density means trees cannot gain a foothold in the space.

We can use shrubs dominantly in a space, or they can be more sparse and mixed with herbaceous plants. In the southeast, I’ve seen shrublands in the mountains, at the beach, and in environments where trees struggle to grow or where they have been removed.

We apply this planting style often to cover a large space with the desire to have minimal management like an island bed of Itea virginica (Virginia sweetspire) or Ilex vomitoria ‘Nana’ (yaupon) in a parking lot. Shrublands are often most effective if we can see over the tops of them. And, we can be creative in integrating perennials into the space to maximize four-season interest.

On Gregory Bald Rhododendron cumberlandense (Cumberland azalea) and Vaccinium sp. (blueberry) form an almost impenetrable layer for walking through save for this trail.

The gravel garden at Chanticleer features a dominant shrub layer mixed with grasses and other forbs.

EDGES

Edges (also called ecotones) are where plant communities shift in response to changing conditions (wet to dry, light to dark, fertile to less fertile). Even disturbance and differences in mowing schedules can create this varied habitat as you traverse a landscape.

Edges are often what we encounter most in a homeowner’s property. The changing light levels as one moves from the house wall outward, the treeline on the fencerow that grades from shade to light, and gradient from the pond to the drier hill all create shifting conditions that can result in different species growing. We can use or enhance edges to tell a story with our plantings. When you walk across a landscape, overt repetitiveness can become boring. Changes in the landscape can keep things varied.

The vegetation in the Green Swamp abruptly shifts from grasses and Liatris pilosa (blazing star) to shrubs and then taller trees.

In Peirce’s Woods at Longwood Gardens, the plants shift from grasses to shrubs to taller trees along this edge gradient.

HEDGEROWS AND FENCEROWS

Hedgerows and fencerows are in a way man-made plant communities. The former was named for the living hedges that separate fields, and the latter from vegetation that arose from not maintaining these barriers. I don’t feel they neatly fall into any of the above categories. They are almost like someone cut a transect, a long brownie bite of a forest or shrubland. They also feel too narrow to be an edge. But, the next time you drive, pay attention to their prevalence. They are everywhere, and these linear plant assemblages are in some cases the greatest opportunities for biodiversity in fractured environments. I like to think of fencerows as nature seeping back into the landscape cracks after the clearing effects of man.

In some cases these are purposefully planted to create habitat. With these spaces you may be unable to turn them into a forest or a woodland, but you can augment what you have. You can add diversity to the periphery of the hedgerow or fence row. And, they can be worthwhile for us to use in gardens as well.

Fencerows and hedgerows criss cross our country, and in some areas may be the last foothold for diversity.

We can bring the concept of hedgerows into the garden, too. At Stoneleigh the wildlife hedge on the right offers a separator between spaces while also providing habitat for creatures in the garden.

WHICH DO YOU CHOOSE?

Here are some considerations on how to place woodies on your own site.

Which do you already have? It’s worth asking what woody plant arrangement do you already have on site and if you can enhance the essence of that woody planting because it’s better to work with the site instead of against it. For example, if you have a small forest filled with invasive species behind your house consider slowly clearing the intruders. When we purchased our property, we had a few trees scattered here and there. Our closest archetype was a woodland with open grassland spaces. So, I’ve set about enhancing that. I planted orchard trees to reinforce that character. And, on our fencerows I’ve started adding woodies to that space like Asimina triloba (pawpaw), Viburnum dentatum (arrowwood viburnum), and Cercis canadensis (eastern redbud) in the hopes to enhance the diversity after clearing out Ligustrum sinensis (Chinese privet).

How much space do you have available? When planting woodies, always keep their final size in mind in relation to the space you have. It may be hard to create a forest in a small backyard with an oak, but we can be strategic and choose trees that will mature at smaller sizes.

Is water available? One of the governing factors for woodies and especially trees is the presence of moisture. In the US, the 100th meridian has long been considered where the US gets too dry going west to be able to support trees. So, when siting woodies it’s important to remember that they will need regular watering during establishment. Before you plant, consider how you will deliver water to the trees and shrubs. Planting in the winter helps to alleviate that strain, but trees may still need water as they establish over the coming years.

Consider repetition to create coherence. In the wild you often don’t just see one tree by itself unless it’s the last tree settlers left centuries ago when cutting the forest in a field. Often we see woodies repeat to create the sense of a forest, woodland, or grassland. Consider when you plant trees to make small groves. Consider planting trees at different sizes. Maybe plant three large Magnolia virginiana (sweetbay magnolia) surrounded by a half dozen gallon plants. It makes it appear as if the grove is growing and spreading naturally.

If you need more ideas, consider joining us for the Botanic Bootcamp session Woodies in Naturalistic Design on May 18!

What Spring Reveals

Spring is always crazy, but this year it has been on steroids. As we reach the end of the semester, I’m taking a moment to reflect on the garden at the end of April (header image). After the haze of the spring semester, it makes me happy to see the plantings around the house reaching peak with a lighter touch this year. I believe getting to this point with a planting is what gardeners desire.

The beds in early April. Streptanthus maculatus (clasping jewelflower) rises above the beds, and Phlox pilosa provides groups of color.

I’m trying to think of what attention we’ve given the beds this spring. There was the February cut back. We’ve made a couple good passes through dealing with cool-season weeds; however, it feels like there are fewer weeds this year, which shows that my attention to covering the ground and weeding over the past few years is paying off. Geranium carolinianum (Carolina geranium) and Vicia sativa (common vetch) tend to be the worst ones. And, I moved a couple of plants around—added two Amsonia tabernamontana ‘Storm Cloud’ (blue star), divided some Penstemon murrayanus (coral penstemon), and moved Fothergilla milleri ‘Redneck Nation’ (Miller’s fothergilla) to a spot I think they will be happier.

Early April at Ephemera Farm. Streptanthus maculatus (clasping jewelflower) rise above the other plants in the bed.

One other change that I made this year was applying minerals to my garden beds. I figure increasing the other nutrients but keeping nitrogen low to limit growth can help optimize plant health. I applied langbeinite, a mineral that contains potassium, magnesium, and sulfur to the bed since soil tests showed that my garden was still low in these nutrients. I’ve noticed fewer instances of mid-day wilting, which is a symptom of potassium deficiency. I also added some rock phosphate, a slow release form of phosphorus to help aid in blooms. Plants appear to be more robust this spring, but that’s just from anecdotal observations I’ve made.

Other than that the plantings have mostly taken care of themselves. But, let me be clear. The garden isn’t perfect. There have been some issues mostly out of my control. About a month ago, we had a hard freeze of 24.6 °F. It slowed down the perennials, but the biennials made it through fine. I saw no damage on Streptanthus maculatus (clasping jewelflower), Nemophila phacelioides (Texas baby-blue-eyes), and Lupinus subcarnosus (sandy-land bluebonnet). My main concern was the impact on our Baptisia alba (white wild indigo). I only ended up having a few Baptisia flowers abort on uncovered plants, and the majority bloomed just fine. I suppose they can survive one night ok, but from our lesson in 2023, two nights is too much.

Nemophila phacelioides (Texas baby-blue-eyes) has started self sowing around in our garden. It makes an early great annual ground cover, but it doesn’t last long in our heat.

My clumps of Arnoglossum plantagineum (prairie Indian plantain) are a bit weaker. They have dense foliage but they aren’t flowering. I haven’t quite figured out why yet. Only three out of my ten or so bloomed, but that could be because the freeze weakened them. I’d hate to lose them, so I’ll be sowing some from seed this year.

The shoots from a single Arnoglossum plantagineum (prairie Indian plantain) rise above our garden.

They could also be weakening from voles. I have determined that voles are likely the core reason I’ve had gaps appear in the garden over the past year. When a dying Penstemon digitalis (foxglove beardtongue) has a hole at the base or a Carex texensis (Texas sedge) can be pulled half out of the soil because there are no roots left, I think it’s pretty obvious. I’ve been reading up on trap options. (And, fair warning. Ugly garden picture ahead!)

Ugly garden picture! Gaps in the garden likely due to vole damage will be filled with plants that have thrived.

But, I am amazed at what they really don’t eat, too. I’m not sure if they just haven’t gotten to them yet or if the plants are resistant to their herbivory, but it seems that some things should have died by now. The gaps have increased but I’m plugging them with plants that seem to be somewhat resistant to voles (as of this writing) like Parthenium integrifolium (wild quinine), Monarda stipitatoglandulosa (Ouachita beebalm), and Boltonia diffusa (doll’s daisy).

Parthenium integrifolium (wild quinine) is a new addition to the garden. It has bold foliage amongst the finer textured plants. Further north, I see these bloom into the summer, but for us they are usually finished flowering by the end of May.

April is now over, and the spring show is starting to conclude. I have made the spring display better over the years by taking notes of changes that I want to make for next year in the winter. Some notes include move crowding plants, thin what is getting too congested, and get more ground cover species so that when the spring cast of characters go dormant there’s less of a gap.

But, for now I’ll enjoy the show. Enjoy a few more photos of the garden below.

And if you want to learn more about designing these type of plantings, check out my class The Naturalistic Planting Primer.

Penstemon arkansanus (Arkansas penstemon) blooms with dainty flowers early in spring.

Phlox pilosa ‘Bonnie’s Pink’ (downy phlox) is a favorite of butterflies like this tiger swallowtail.

Callirhoe alceaoides (white poppy mallow) has a knack for weaving itself through perennials.

Penstemon murrayanus (coral penstemon) is one of my favorite perennials. It has such a brilliant color and such interesting foliage.

I love the glaucous blue leaves that wrap around the stem of Penstemon murrayanus. We call that character perfoliate.

And, when they bloom they have racemes loaded with coral funnels.

These purple form Tradescantia gigantea (giant spiderwort) are always a strong color contrast in the garden.

I’ve enjoyed over the years watching the Penstemon digitalis (foxglove beardtongue) increase in number.

Baptisia alba (white wild indigo) is a primary plant in our garden in the spring. The spires rise above the plantings.

Every evening we enjoy watching American bumble bees visit the flowers of Baptisia alba (white wild indigo).

A glimpse of our garden looking toward the house.

Tephrosia virginiana (goat’s rue) is a wonderful underutilized native with lovely yellow and pink flowers.

Asclepias viridis (green milkweed) is our most populous local milkweed species.

Phlox ‘Minnie Pearl’ (phlox) is a wonderful seasonal filler amongst Osmundastrum cinnamomeum (cinnamon fern) and the foliage of Parthenium integrifolium (wild quinine).

The garden looks good still as we leave April behind and welcome May.

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KEEP GROWING

Protecting the Garden from a Freeze

My heart sank when I saw it. The forecast two Tuesdays ago showed 35 °F seven days out.

The day before, Magnolia and I had planted beans and squash because when I looked at the two week forecast, there was nothing below freezing. But models update overnight, and my worries that the early spring we'd been experiencing would be nipped before the last frost date appeared to be coming true.

Throughout the week I continued to monitor the temperature, and after a couple of days, Time and Date was saying that we were going to have a low of around 21°F Tuesday morning. Talk about gut wrenching. Other weather apps and websites weren't claiming that yet, but their forecasts would drop over the coming days until we received an official freeze warning.

I had felt this pain already a few years ago in 2023 when Pam Penick was coming to shoot our garden for her book Gardens of Texas. We had two days of 26 °F after several weeks of warm weather. The Baptisia (wild indigo) had already emerged, the persimmons had flushed out, and my azaleas were in full bloom. All of them and more got burned. The Baptisia failed to flower correctly that year, and I even lost most of my blueberries. I can weather these events if they happen once every 10 years, but after having this just happen three years ago, I was ready to take matters more into my own hands instead of waiting and seeing.

Protecting plants isn’t new to me. Season extension has been an interest of mine since my teenage years. As a gardener in Tennessee where the season was shorter, I played around with covers, double covers, and other strategies to protect plants. I was mainly focused on trying to extend the end of the season into the winter (one year I got spinach to survive 9 °F!), but we can also extend the season by protecting plants in the spring. And, it’s not just limited to the vegetable garden or seedlings. There are other methods we can use to protect plants from cold weather.

So after catching the red eye back from speaking in Seattle and getting home around 8:00 AM last Sunday morning, I went outside to set about protecting what I could after a short nap. I got everything in place so that I’d be ready Monday night. Three forecasts I looked at Monday evening showed 29 °F, 27°F, and 21°F. My guess was we would be 24 °F.

I awoke Tuesday morning to find that we were 24.6 °F. Boom! While it felt great to know our area well enough that I could guess the temperature, I dreaded what I might find outside.

However, I was delighted that my season extension efforts mostly paid off. Here’s the different approaches I used this week along with if I would repeat them.

Covering vegetables with frost cloth and Christmas lights (absolutely yes!). It’s funny. In a bit of fleeting optimism, I had put my floating row cover up just before I saw the first hint of a coming cold front. I dragged it back out, and put the frost cloth back up over my luscious potatoes (seriously, the best crop I’ve ever had!) and the beans and zucchini that we had just planted. But, this time I added five strings of Christmas lights around the tender plants. Years ago when we had a late frost, it was enough to protect my tomatoes, and I figured it would work again. I have to give credit to Lindsay Kerr, who gave me the idea of using the Christmas lights years ago. One of the issues we have in Texas is if we wait until we’re frost free we run the risk that we will have a hot summer that will slow plant growth.

The success of this method with the beans and zucchini also has me rethinking when to plant my warm-season crops during the yearly tug of war between winter and spring. Usually I try to wait to plant warm-season crops until the last absolute frost date, maybe even two weeks past that. It was what I practiced in Tennessee to optimize plant growth based on weather. But in Texas, we are racing to get plants to grow and yield before we get so hot in the summer. I'm now considering jumping the gun and extending the season in the other direction—starting earlier in the spring under cover to help get crops going before the heat arrives.

I might also look at attaching the Christmas lights directly to the hoops to keep them suspended up off the ground. I just have to watch to make sure wherever I put them doesn't risk ripping the fabric.

Potatoes are still alive the morning of the freeze with the floating row cover and Christmas lights.

Zucchini seedlings made it with the Christmas lights.

A few days later, bush beans have emerged well.

A few days after the freeze, the potatoes look healthy. Note a few brown leaves where the foliage touched the frost cloth.

Covering blueberries with blankets and Christmas lights (absolutely yes!). I threw two strands of Christmas lights on two blueberry shrubs, and then covered them with old blankets. The recommendation with blankets or other coverings is that it has to cover the plant all the way to the ground. However, the blankets weren’t that big, which meant they were suspended on the plants with a gap at the base. The Christmas lights were able to produce enough warmth that it protected them! The two blueberries I lit and covered are still in flower now a few days later, and the fruit appear just fine. There’s another blueberry bush that I did not cover as a control a few feet away, and the fruit have turned brown on them.

After removing the blankets, the blueberries looked fine with the Christmas lights.

A few days after the freeze, bees are still working the blueberry flowers.

Running an overnight sprinkler on the persimmons (maybe, but probably yes). Water can be an effective means to prevent plants from freezing. As water goes from a liquid to a solid, it releases latent heat, and that heat is enough to protect plant tissue. It’s not just large scale farmers who use this method. My great-grandfather would go out in the middle of the night and run a sprinkler on his strawberry patch to protect the flower buds from a late freeze. Around 10:00 PM, I saw the temperature had already dropped to 32.4°F, so I went outside and turned the water on. To my dismay, the water in the hose had already frozen. I turned it on and noticed a slow trickle out of the sprinkler. There was enough water moving through the hose that it was able to melt the ice, and after about two minutes or so the sprinkler was running. In the future, I'll probably try to start it a little bit earlier.

The next morning the tree was covered in ice (header image). Would I do this approach again? Most likely. It sure is nice a few days later to see verdant leaves and emerging flower buds on the persimmons. The one issue, though—and it hit me around 2:00 AM lying in bed—is that the weight of the ice on the plants could be catastrophic. I actually lost a couple of small branches on one tree. The loss didn't disfigure it in any meaningful way because I've been pruning them healthily over the years, but it's something to consider. Am I willing to lose a portion of the tree due to ice load just to save a year’s crop?

A few days later, the persimmon trees I sprayed are still green with minimal leaf damage…

…while the one I didn’t spray water on looks rough. It should rebound like they did a few years ago.

A gash on the persimmon tree from the ice load. This damage makes me question if I would spray them with water again.

Protecting Baptisia with autumn leaves (no). Baptisia alba (white wild indigo) is a crucial primary plant in our spring garden. After the 2023 freeze, the blooms failed to form right, and it’s absence in the upper layer in our garden was quite apparent. So, I built chicken-wire cages about 19 inches wide (5 ft round) and filled them with leaves. I was inspired by colleagues further north that encage their bananas and other tropicals with autumn leaves, but I would not do the leaf cylinders again. They were too thin. I don't think there was enough insulation, and some of the Baptisia were already emerged 12-to-18 inches. I'll go back and inspect each Baptisia clump. I'll cut off anything I think was frost damaged, because I already know the inflorescences that had emerged are gone. That will help to encourage the plants to direct their energy into the buds that were more protected down near the base. In some cases, I may actually have to cut the entire plant back and hopefully force some lower dormant flowering buds out.

The Baptisia shoot on the left is damaged and blackened from the freeze while the right one looks ok.

Covering Baptisia with a tub and Christmas lights (absolutely yes!). There was one Baptisia plant that was too tall to cover with a cylinder at all. For that one, I got a leaf collection tub, put twinkle lights underneath it, and that plant made it through just fine. So in the future, instead of doing the leaf cylinders, I'm going to get 5 gallon buckets or some type of tarp teepees. I can put stakes in the ground around the Baptisia, drape the covering over them, put Christmas lights underneath, and run extension cords through the garden connecting everything. I know it sounds complex, but it makes buying those 20 strands of Christmas lights on clearance the day after Christmas worth it!

Covering the nursery plants with tarps (absolutely yes!). I do this already, but I wanted to mention it for those of you unaware. Even when we have steep dips in temperature during the winter, I’ll cover my seedlings with a tarp. They made it through just fine.

Bringing tender plants inside (absolutely yes!). I also brought tender plants like tomato and basil seedlings and my Sanseveria inside the garage overnight. No question I would do this again.

If we continue to have warming springs with sudden eruptions of cold further south, season extension will be crucial to protect plants. One night can ruin so much, but it still amazes me that plants can make it through with no damage.

Weeks like this one are a reminder that gardening is always a delicate dance with nature. You can cover, wrap, water, and light your way through a hard freeze, and sometimes it works beautifully. But the plants that worried me least were the ones I'd chosen well in the first place. Take these Lupinus subcarnosus (sandy-land bluebonnets) below. Sure, they looked rough Tuesday morning, but now they look fine.

That's the quiet power of plant selection.

If you want to go deeper on that idea, I'd love for you to join me Monday, March 23 2026 at 6:00 PM Central for my next Botanic Bootcamp session—The Power of Plant Selection. Click below to learn more and to access a discount code.

Lupinus subcarnosus (sandy-land bluebonnet) shrugged the freeze off.

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Keep Growing

Considering Narcissus

There are few things that feel as good in life as that first warm stretch after a cold winter.  

That’s what we enjoyed this past weekend here at Ephemera Farm.  I finished the great cutback, and the garden is cleaned of last year’s growth.  In the areas I cleared a few weeks ago, the early foliage of Arnoglossum plantagineum (prairie Indian plantain) and Rudbeckia maxima (giant coneflower) are already making a strong presence at ground level.

And, the plantings are beaming with Narcissus (daffodil).  They are one of the non-native species I use to fill an empty gap at the beginning of the season.  My naturalistic plantings can look quite devoid of plants until early March when the first wave of color from Phlox (phlox), Glandularia (rose vervain), and Lupinus (bluebonnets) start.  The Narcissus glow on both the bright and solemn days we have in February.  

It’s taken me a few years to figure out which species will grow well here in east Texas where we have less cold than further north.  I now have a handful of varieties that have proven to bloom well.  

Last weekend was a good time to pause and admire their attributes.  I was reminded of how important the process of plant selection is from my friend Molly Hendry when we spoke together a few weekends ago in South Carolina.  She shared while she was at Great Dixter, Fergus Garrett had grown 10 different types of Muscari (grape hyacinths) in pots and then had the interns evaluate which of them were the best.  They were asked to consider flower, form, foliage, how they would fade, and more, and they were then to tell Fergus which were the best.  I admired that great attention to detail. It clicked with me how simple this approach was for us gardeners to examine a plant's attributes, and it's something I've been thinking about as I prepare for the next Botanic Bootcamp on the power of plant selection. So, I walked the garden collecting flowers and foliage to compare.   

Narcissus pseudonarcissus (Lent lily) has been the dominant daffodil I’ve used in my beds.  The light yellow flowers are not too overpowering for the space.  And, after they finish flowering the thin blue leaves echo well with Rudbeckia maxima and Eryngium yuccifolium (rattlesnake master).  I make sure I go through and remove the seed pods so that they don’t seed around and that redirects energy back into the bulb.  

In the core beds near the house, Narcissus pseudonarcissus blooms with a soft yellow.

I have debated over the years if I have one or two different types of Narcissus tazetta (tazettas), but after amassing this collection, I can see the differences.  Both were nameless backroad rescues. One has a darker cup and thinner foliage, which could be ‘Grand Primo’.  The other has a much larger presence in the garden with its flowers and larger leaves. Greg Grant suspects it is an old timey cultivar called ‘Grandiflora’.  On this one, I noticed a bit of damage in the middle of the thick blades where they bend. My guess is that spot is where the sun shines on the freezing mornings, and the tissue burned a bit.  Because the foliage can show winter damage and the volume of blades produced, I’ve decided to not plant them in any beds. They can start looking too flimsy after flowering. Instead I hoard them under my blackberries.  I love using them here to smother the weeds out. 

Narcissus tazetta ‘Grandiflora’ cover the ground under our blackberries with their thick foliage.

Most of the rest of my Narcissus have been in trial beds waiting to see where I can use them most effectively.  ‘February Gold’ is a new one I bought a few years ago, and I am ready to commit to planting them into beds on the western side of the garden where I have more warm colors from Salix ‘Flame’ (willow) and Cornus amomum ‘Cayenne’ (silky dogwood).  Over the period of a few years, I watched as other bulbs planted at the same time like ‘Tête-à-Tête’ and ‘Jetfire’ melted away, but ‘February Gold’ continued to weave more golden flowers.  For us it’s early and started blooming February 5 this year, even beating Narcissus pseudonarcissus that opened on February 9. The green verdant leaves are different than the many others I have with a bluish cast.  For me the leaf color is the driving factor of putting them on that side of the garden.  The green foliage pairs better with the warm colors.

I have bulked up hundreds of Narcissus × odorus (campernelle), and I’m eyeing putting them on a hillside on the eastern part of our property where it stays wetter just down from our ‘Ann’ Magnolia (hybrid magnolia).  The flowers are a strong yellow, and they have these thin green leaves that aren’t as strappy as others.  Perhaps this year I’ll be able to check that off my list.  

Another perspective of the flowers so you can enjoy the insides of the coronas.

I love ‘Carlton’, but the large flowers are a bit overpowering, and they are also an intense yellow.  I haven’t quite decided where I want them to go yet, but I’m leaning toward mixing them in with the campernelles so that they can play a bit off the same color with just different shapes.  

I have two Narcissus that feature a color shift between the petals and the corona.  I love ‘Ceylon’.  The orange cups are so striking on this Narcissus against the yellow petals, and it is one of the only orange cup types I’ve had success with so far.  And I’m delighted that ‘Ice Follies’ is growing well for me.  I have seen it here and there in east Texas and finally decided to give it a try.  It was one that I grew back in Tennessee, and I love how the petals fade from a creamy yellow to almost white while the cup holds a buttery yellow color.  I still haven’t decided where to place then, and that’s ok.  I can enjoy them in the patch for now in their holding beds.  

Foliage and flowers to consider mixing with Narcissus left to right: Rudbeckia maxima, Eryngium yuccifolium, Ipheion uniflorum (starflower), Arnoglossum plantagineum, and Leucojum aestivum ‘Gravetye Giant’ (summer snowflake).

Before I gathered them into a bundle for taking inside, I walked the garden and collected foliage and flowers from other plants that they will share space with in the coming weeks before going dormant.  I focused on plants that have hints of blues and greens to see if there are combinations that I should further consider.

Many solo planted bulbs have bulked up over the years, and I’m keen on dividing some clumps this spring and moving them around. And, after I put them in their new spots, I imagine the joy they will bring in future springs. But for now, I’ll enjoy this one.

Site Inventory and Analysis

Want to Learn More?

I’m hosting a live Botanic Bootcamp session, Reading the Land for Smarter Planting, on Monday, February 2 at 6 pm CST. You’ll learn how to read a site before you ever pick a plant. We’ll discuss seeing visual and experiential aspects, understanding light, soil, and water, and more so your plantings are more resilient, intentional, and purposeful. This session will give you the framework to make better planting decisions from the start.

What does it mean to read the land?  To me it starts with taking account of everything that is present and to imagine what the site can become.  

Reading the land requires us to have two ways of seeing the landscape, what does the landscape offer and what potential does it have.  We call these two mental modes inventory and analysis.  

Sure, this process isn’t as glamorous as picking what plants to grow and how to arrange them.  Often we want to rush into design, but doing inventory and analysis first can save you so much headache later on. We can prevent plant death and replanting, blocked views, flooded beds, wasted money, constant maintenance, and much more.  And it doesn’t have to be a new garden that you are assessing.  It could be one that you’ve lived in for twenty years.  

Thrash Early

Inventory and analysis are part of the process that Seth Godin calls thrashing, where we get things right early in a project.  We take stock of what we have and what direction we want it to head. We bring everyone in on a discussion to make decisions early.  For some, it may be a husband-wife team.  For others, it’s multiple stakeholders and people from the public.  However, it is better to thrash early than wait until the project is 95% finished to realize we missed something.  

Site Inventory

With inventory, we are asking what is present.  It is objective, descriptive, and observational.  We are making no judgments yet.  Just the facts, ma'am.  

For me, site inventory breaks down into six categories:

• Physical — buildings, hardscape, utilities, topography, geology

• Biological — flora and even fauna on site, where types of plants congregate, plant communities

• Soil — soil texture, soil drainage, soil nutrient levels and pH

• Weather and climate — temperature, rainfall and where water pools, wind movement across a site, microclimates, where things feel warmer or cooler

• Light — how it shifts over the day and over the season, sun angle and reflection

• Visual and experiential — vistas and long views, the mood of the site, the spirit of place, and natural movement paths

Site Analysis

With the inventory complete, we begin the analysis to consider what this place can be.  What can I do with this space? Analysis is interpretive, evaluative, and creative.  We begin to introduce goals and priorities, and we begin to see the site through human desires and wishes.   We start considering constraints and opportunities and can we work with things or will we need to move against what we see.  

I should stress that analysis is not design yet.  There are no plant lists, layouts, or styles decided on yet.  You are just trying to see what you can do with the possibilities and constraints of the site.  

So, just a few ideas for the same six categories

• Physical — Do you hide or accent the house?  Are there places for more entertaining options? What does the lay of the land dictate about movement or erosion?

• Biological — Should trees stay or go?  Does the vegetation have a natural tendency toward an archetype? Should it be allowed to progress or interrupted? Are there plant communities, animals, or ecological processes that need to be accounted for?

• Soil — How can soil fertility and texture influence what plants grow?  What can we do with high fertility or low fertility? Does soil drain well or is it mucky?

• Weather and climate — What does it mean that this microclimate is warmer or cooler? Should we plant species that will move with the wind, or do we need a wind break to calm the air?

• Light — How can you play with light?  Do you want more light or less light?

• Visual and experiential — Are there potential views you can create or enhance?  What can you do to create feelings of prospect and refuge? What are the landscape preferences that we can embrace and enhance in the space?

Analysis isn’t limited to one idea.  It may be worthwhile iterating through options to consider what all possibilities exist. For example, when we bought our property, we had a large open space beside our house that could have become anything.  I could have planted a vegetable garden, more trees for shade, or an orchard. 

I noted the space’s proximity to the house, the sandy soil, how water moved across it, and how it wasn’t saturated like other parts of the property.  It was mostly turf, which meant that it was ripe for planting.  Light would interact with it throughout the seasons and for most of the day. Being in an elevated spot, it offered good views of other parts of the property, and I didn’t want to interrupt that.  I knew I wanted a naturalistic planting, and inventory and analysis helped me reach the conclusion that this spot was perfect. Even when I consider any changes to the garden, I keep these initial observations and ideas in mind.  

Our blank slate of a yard in 2017. It took me time to read the land, to inventory what we had, and to analyze and think about what I wanted this space to become.

Several years later, here’s what I get to look at. It all starts with inventory and analysis.

Conducting Your Inventory and Analysis

Doing your own inventory and analysis is easy. You can easily take some blank paper and sketch what you see.  Or, find the place on Google Maps, capture a screen shot, paste it into PowerPoint, and make the image 50% transparent.  Then you can print off a few copies and walk around the site writing or drawing what you see. 

You also don’t have to do inventory and analysis just once.  You can repeat the process over the course of a year.  I know that most designers are under the constraints to only visit once or twice, but it can be hard to truly know a site until you’ve experienced it for a trip around the sun.  You don’t know yet where the last light lingers on the winter solstice.  Or, how the water moves across the property during a deluge. Time and a few tricks that I’ll discuss in Reading the Land for Smarter Planting will help you.

Remember, inventory describes and analysis decides. And, once you’re done, the magic can begin as you start to create the garden of your dreams.  

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KEEP GROWING

What is Plant Sociability?

Change the way you see plant patterns for better design. Designing with Sociability will help you better understand how plants spread, how we can use sociability to create better plantings, and more. Plus, attendees will get a handy-dandy plant sociability list of plant species.

One of the challenges that gardeners face when creating naturalistic plantings is how to arrange plants.  Questions arise about what species should be combined together and how we can place them to maximize ecology and aesthetics while also minimizing maintenance.  

If we look to the natural world for inspiration and observe how plants grow in nature, we will see patterns.  One way that horticulturists have figured out how to describe these patterns is with the concept of plant sociability.  

What plant patterns do you see in this plant community? Do you see solo viburnums, waves of red blueberries, patches of grasses, and spears of goldenrods? We can explain these with sociability.

So, what is plant sociability? 

There are a few sources that give us a deeper understanding.

In Planting in a Post-wild World by Thomas Rainer and Claudia West where I first learned of this concept, they stated that plant sociability is “how far plants in the same population grow from each other,” and it “offers a good model for distinguishing which plants should be massed versus which should be placed individually.”  

Brandon George’s incredible capstone project stated that plant sociability is “a measure of the distribution pattern and organization of the [plant] species.”

Nigel Dunnett added in The Dynamic Landscape that sociability helps us understand “the degree of massing that the species shows in the wild.”

And in the original Hansen and Stahl’s Perennials and Their Garden Habits, they dance around a definition saying that “it remains important to group the various species according to their inherent sociability, always taking nature as a guide.”  

What they lack in defining it they make up for by creating a sociability classification system.  Hansen and Stahl gave us five levels along a gradient to classify sociability.  Level 1 is for plants that occur solitary, and Level 5 is for thick stands of a species. From their book they give these categories,

• 1 singly or in small clusters

• 2 small groups of 3–10 plants

• 3 larger groups of 10–20 plants

• 4 extensive planting in patches

• 5 extensive plantings over large areas

There are also a few pages of plant classifications along with how far apart to space plants per meter.    

Outside of these sources, there’s not much available in the research literature on plant sociability, which is a shame.  As one newsletter reader emailed me, everyone seems to talk about this magic approach to grouping plants and yet there is much lacking on the approach.  So, here are a few things I keep in mind.  

A SIMPLE ANALOGY FOR PLANT SOCIABILITY

I like to think about sociability like watching how people sit on an empty plane with no assigned seats.  

Some people come in and space out as they sit solitary.  Others get on and claim rows as small groups, say a family of four with grandparents in tow.  And, then there’s the whole sports team that takes up a third of the plane all sitting together, weaving themselves around the singletons and small groups.

On the plane, people sit in these patterns based on their connection with each other (family, relationships) and the environment (what seats are available when purchasing; the resources needed (aka dolla dolla bill y’all) for a first class versus a middle seat).  

For plants, they grow in patterns because there is an interaction with their connection to each other (in this case plant genetics influencing how they spread and reproduce) and the environment (what spots are available to grow; amounts of resources of light, water, and nutrients; etc.), too.  

Unlike our plane example where the greatest in number would be those flying solo or in small groups, plants with low sociability usually constitute the lower numbers in the community, and plants with higher sociability tend to be more dominant and plentiful.  

Pick your seat. In this space we see Asclepias tuberosa (orange milkweed) spaced out as a low sociability plant.

Don’t be confused by the numbers

I’m not trying to reinvent the wheel here, but I think that numbers Hansen and Stahl use can be lost on some people because they have to memorize what 1 or 5 means.  So I like to add the descriptors to sociability levels—very low (1), low (2), medium (3), high (4), and very high (5).  I think that it helps amateurs better think through whether their plants should be treated as loners, light minglers, or gregarious party animals.

Numbers can also shift slightly based on growing conditions.  Higher levels of sociability are usually associated with richer resources. For example, a wet site might shift a low (2) or medium (3) sociability up to a high level (4). But, the extremes usually don’t move to the other end. A species with very low sociability will likely never reach very high sociability, and it would look a bit odd if it did. And, species that have very high sociability planted as a single plant aren’t living up to their full potential. Give them 40 years and then they’ll be carpeting the ground.

This planting of Yucca (yucca) was done for a modernist effect, but it looks a bit odd because as a low sociability species it should not be planted so close. It would have been more effective to randomly scatter clumps in the Sporobolus (prairie dropseed) matrix.

Sociability HELPS gardeners DESIGN AND PLANT BETTER

I think too often we gardeners are in the habit of creating gardens that are plant collections of single plants or as Tony Avent calls this approach, “drifts of one.”  I know that I have been still am guilty of it. I mean, it wasn’t my fault I had to grow and trial so many different species to see what would die, survive, and thrive here in east Texas.  At least, that’s what I tell myself.

Now that interest is growing in naturalistic planting, we can’t apply that same approach. We can’t plant singletons far apart and then just pour mulch around the plants. There needs to be some level of coherence and legibility. Otherwise, the planting can look chaotic.

When you consider sociability in design, you’re not going to the garden center and buy one each of 40 different species.  Instead, you pick a few plants with very low/low sociability to stand out, a few groups of medium sociability to keep the seasonal interest going through the year, and many plugs of the high/very high sociability patch formers. 

A naturalistic planting at Epic campus in Wisconsin. Note how some species like the Symphyotrichum (aster) are grouped together while others occur singly.

It may be hard to invest money on 30-50% of the plants that are going to just be green groundcovers with high/very high sociability. And, sure you could wait for those plants that typically grow in higher sociability to increase in number, but having one Carex texensis (Texas sedge), Packera aurea (golden groundsel), or Pachysandra procumbens (Allegheny spurge) is just going to look weird.  We are used to seeing them in larger groups instead of isolated.

Sociability also helps us understand and anticipate how a species will spread and perform in the garden. For example, Helianthus angustifolius is a Level 4 (high) sociability plant. I planted two a few years ago in my garden, and they quickly began to spread via rhizomes and seed. Now I have tons of it.

And, something like Yucca rostrata that has lower sociability will look best if it’s more isolated. I shouldn’t anticipate it quickly spreading around.

Helianthus angustifolius (swamp sunflower) blooms in autumn. Even though I planted a couple, this high sociability species has made its presence known in my garden.

PRACTICE SEEING SOCIABILITY

If this concept is new to you, start practicing applying it today.  Walk through a natural area or your garden, and pay attention to which species occur in groups small or big group and which plants stand alone.

That mental shift will help you start seeing your plantings as a community, and that’s the first step toward designing with sociability. Once you start seeing those relationships, you’ll never look at your garden or nature the same way again.

New and Mature Gravel Gardens by Jeff Epping

A few weeks ago I had the privilege of traveling to Madison, Wisconsin to speak to the Wisconsin Hardy Plant Society. My friend Jeff Epping offered to show me around the day of the presentation. If you don't know Jeff, he is the retired director of Horticulture from Olbrich Botanical Gardens. He has risen to prominence for his design work with gravel gardens, and really he is one of the foremost experts on this approach to planting in the US.

Gravel gardening has gained interest in recent years due to the desire to have a beautiful naturalistic garden with limited maintenance due to reduced weed pressure. The upfront costs are more expensive, but corporations, cities, and campuses can actually save money in the long run with these planting approaches.

Ultimately a layer of gravel—preferably an angular gravel—is put on top of the soil, and then plants are planted into that. Because the gravel layer introduces stress against competitors, more species are usually able to be planted in a gravel garden and survive over time. I should also clarify that gravel gardens are not the same as the rock mulch you see in gas stations and fast food restaurants.

Jeff took me to see a newly planted gravel garden at the Madison Parks Lakeside Offices that was just installed in the summer of 2024, and one at Olbrich Botanical Gardens that was planted in 2014. I think it’s helpful to see photos of a fresh planting and one that has had time to mature, so enjoy the comparison photos below.

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Madison Parks Lakeside Offices

Jeff noted that while space between the grit was visible now, it would fill in.

Eryngium yuccifolium (rattlesnake master) and Liatris ligulistylis (northern blazingstar) are a good emergent layer for the gravel garden.

Even this little strip next to the parking lot featured a gravel garden planting.

Dalea purpurea (purple prairie clover) was in bloom in the garden.

A dried Allium (wild onion) umbel offers late season interest.

I noted how richly colored the Bouteloua curtipendula (side-oats grama) were in the gravel garden. I love their safety cone orange-colored stamens.

A close-up of the grit that Jeff uses. It's a quartzite material and doesn't decompose and has limited fines to reduce weed growth.

Jeff commented how they didn't want the whole area to be a gravel garden. So, they did a Sporobolus heterolepis (prairie dropseed) meadow.

Sporobolus catches the early light. I noted how much taller and lusher prairie dropseed is in Wisconsin than in Texas.

Sporobolus heterolepis (prairie dropseed) glimmers in the morning light.

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The Entrance Gravel Garden at Olbrich Botanical Gardens

This gravel garden is over ten years old and features a healthy mix of herbaceous plants. Silphium terebinthinaceum (prairie dock) was such a prominent species in the gravel garden with its bold foliage and tall inflorescences.

Liatris ligulistylis (northern blazingstar) blooms among other gravel garden companions.

A painted sign shares how wonderful Silphium terebinthinaceum (prairie dock) is as a plant.

Euphorbia corollata (flowering spurge) is a dynamic filler for late summer and early fall color.

A bee hotel provides nesting habitat and an educational opportunity for visitors.

Liatris ligulistylis (northern blazingstar) pops out of the gravel garden.

The effervescence of Calamintha (calamint) is a foil for the seedheads of Echinacea (purple coneflower).

A distance shot of the gravel garden gives an overview of the growth habit of many perennials.

If you want to learn more about gravel gardens, my next post in two weeks will feature another planting Jeff installed at Epic Campus. Stay tuned!

The Good, Bad, and Ugly of Summer

This summer hasn’t been too bad weather-wise here at Ephemera Farm.  I actually had to look at our weather station to see how many days we’ve broken 100°F.  Even this morning was 68°F.  

Normally, there comes a point where the spigot from the sky turns off, but this year that hasn’t happened.  We’ve had a regular amount of rain, minus a dry spell here and there. We have no drought, but there’s been an outbreak of fungal issues and weeds.  

Good years are just as helpful to evaluate the garden and see what thrives as bad years.  What can stand up with abundant rain and wet soil?  What flops?  What has clean foliage?  And, what looks like trash? I’ve learned every summer there inevitably will be the good, the bad, and the ugly. Some year, the categories plants fall into changes. Other years, it’s pretty consistent being good, bad, or ugly after July and August.

There are some plants I’ve learned go dormant regardless of the moisture level.  Early on as I was learning what would grow well in Texas, I assumed that plants prematurely halted growth with the summer dryness, but seeing decline followed by dormancy in wet years has changed my thinking.  

Take Baptisia for example.  Every year no matter how much rain we get, Baptisia alba (white wild indigo), Baptisia sphaerocarpa (yellow wild indigo), and Baptisia australis var. minor (dwarf wild indigo) usually go dormant in early August.  Phlox ‘Minnie Pearl’ (phlox), Stokesia laevis ‘Peachie’s Pick’ (Stokes’s aster), and Clematis reticulata (netleaf leather flower, header image) show a similar pattern. 

Baptisia alba

Stokesia laevis ‘Peachie’s Pick’

Phlox ‘Minnie Pearl’

While I know Piet Oudolf says brown is a color, too, this early in the season to have blacks and browns amongst so much green isn’t welcome.  We still have 90 days until frost and our show of asters, sunflowers, and salvia to come.  So, where the necrosis detracts, I prune it out to freshen the garden.  

Some plants fade okay like Monarda stipitatoglandulosa (Ouachita bee balm) and Eryngium yuccifolium (rattlesnake master).  For the former, the brown seed heads are supported on mostly still green plants, and for the latter, there is still a good amount of green in the leaves and inflorescences.  

Monarda stipitatoglandulosa

And, then others like Symphyotrichum oblongifolium ‘Raydon’s Favorite’ (aromatic aster) look rough in these wet years.  The tips are green, but there’s a good amount of foliar dieback inside the plant.  I’m considering applying an organic fungicide next year to see if that would help.  

I have also focused on planting the good—more visually appealing plants at this time of the year to fill the gap.  We have height from the verdent seed capsules of Lilium formosanum (Formosan lily) that finished blooming just a few weeks ago, and the rains have spurred on a second flush of Hymenocallis occidentalis var. eulae (summer spider lily) blooms.  

Hymenocallis occidentalis var. eulae

Silphium perfoliatum (cup plant), Physostegia virginiana (obedient plant), and Boltonia diffusa (doll’s daisy) all look stellar with no issues with foliage.  Silphium has bloomed all summer, Physostegia got started flowering in mid-July and still goes, and Boltonia foliage haze is just starting to show some of its darling flowers.  

Boltonia diffusa

But, there are still gaps. The spring is so verdent with good ground coverage.  I keep thinking that I’ve done a good job closing the gap, but then August comes and I’m wondering why is everything bare under this Baptisia?

Part of the gap could be I’m losing plants.  My dense clumps of Pycnanthemum tenuifolium (narrow-leaf mountain mint) have slowly been disappearing, and I’ve lost two Stokesia.  My suspicion is voles, which is odd for them to go after mints.  But, I also ponder if I have a root fungal disease that is becoming problematic.  I go to pull on the Stokesia, roots are still in the ground, but it looks like they’ve just rotted.

If you have any ideas of the cause, please pass them along.  For now, I’m planning on what to plant in these spots when cooler weather arrives. It won’t be long now.

Oudolf Garden Detroit

“Oh, no! I forgot my camera!” I said to Karen. She was sitting next to me on the airplane some 30,000 feet in the sky as we were headed to visit her sister in Michigan. Part of the trip was to visit the Oudolf Garden on Belle Isle, but with dad brain and an early departure, putting it in my backpack slipped my mind.

“Can you take pictures with your phone?” she asked, trying to soften the blow. “Yea, I guess,” I replied.

My camera has long been my trusty sidekick visiting gardens around the world. But, leaving it behind would force me to pause and actually appreciate the garden.

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We drove down on Friday, the first day of summer, to see Belle Isle with Karen’s sister’s family. Parts of the park at Belle Isle were originally designed by Frederick Law Olmsted in the late 1800’s, and after a letter from the Garden Club of Michigan, Piet Oudolf was asked to come in and put his signature on a three-acre spot some 150 years later.

We approached the garden from the east side, the side near the conservatory. It was here that we met up with my friend Lindsey Kerr, an extension agent with Michigan State University.

THE GARDEN BEDS

Upon entering the garden, the classic Oudolf style was immediately visible. Even though the garden is still young and will celebrate its 4th anniversary in August, the plantings had largely matured and filled in the space quite effectively. The long vistas provided a wonderful layered effect. From studying the designs in Piet Oudolf at Work and on the Oudolf Garden Detroit website (which I will add is one of the best public garden websites I’ve visited for identifying a garden’s plants based on plant list and interactive map), it became apparent that Piet used a simple approach in designing the space. There would be three primary planting schemes (A, B, and C) across the 15 beds, and each bed with the same letter would mostly repeat the plants. So, perhaps one could consider it to be a modular list of plants that then go into each bed.

Just inside Oudolf Garden Detroit the diversity in the beds becomes apparent.

A view of the beds looking toward the conservatory. From this perspective the turf walkways in between largely fade from view.

Repetition of plants and colors across the site helped to make the garden feel cohesive. Echinacea pallida ‘Hula Dancer’ (pale coneflower) danced across the garden, and in the distance more are visible.

One of the farthest perspectives of the garden from the conservatory.

From this angle looking toward the river you can see the pathways in between the beds where a bench allowed visitors to sit and appreciate the garden. Allium obliquum (twisted-leaf onion) provides a strong presence in this space.

RAIN GARDEN

Lindsey took me to the rain garden on the west end and showed the simple woodland grove that was planted to help filter rainwater off the road. I assumed this side to be the main entrance, and having this more verdant spot reminded me of the pond garden that one sees when entering Oudolf Field at Hauser and Wirth. Right behind the rain garden was the bird border where woody species were planted to help provide food and habitat for birds.

The rain garden looks quite verdant, and in mid-June it is more quiet than the other beds.

Carex bromoides (brome-like sedge) was used as the groundcover layer in this section of the rain garden with Viburnum nudum (possumhaw viburnum) flowering.

MATRIX PLANTING IN THE TRIANGLE BED

We made our way back across the site admiring the plants and combinations as the Red-wing Blackbirds sang their Conk-la-rees and took me back to my childhood days in Tennessee. At the far east edge where we first met up was a matrix planting in a triangle bed that we both admired. It was simple in concept and design and very effective.

The airy flowers of Gillenia trifoliata (bowman’s root) and bold leaves of Darmera peltata (umbrella plant) contrast well with the sedge groundcover.

Further into the bed irises rise out of a sea of Carex.

Lindsey and I parted ways as the rain showers started picking up. I was headed to meet up with Karen and crew, but I decided to huddle under a tree near the matrix planting as radar showed it to be quick to pass.

I noticed a volunteer mowing grass with an electric mower and asked if she knew what the Carex was that made up the matrix. She said no, but one of those green shirt people can help. They were back by the middle of the garden near the Nancy Brown Peace Carillon that towered over the site. They were leading a tour to what appeared to be one of two high school groups. I figured it wouldn’t take long to ask, but I got sucked into their story about the space.

Then, Richard Thomas who is the head horticulturist at Oudolf Garden Detroit walked up with his group. They asked the students what they had learned, and the students commented about the pollinators. Richard then started talking about the history of the site. I remembered that they had a big flood early in the development. He commented that if they had started just a few months earlier that all the plants would have likely been washed away. This flood forced them to move soil up and build up where the plants would be planted.

As I listened I realized that the group of about 20 students would be helping plant Sporobolus heterolepis plugs into the area around the carillon. This area will flood occasionally. They had goats clearing out the middle section around it, but these plants would go in a newly planted area outside. This lower riverside area had issues with invasive species, but their efforts to bring them under control had worked tremendously.

As Richard stepped aside, I caught him to say hi, introduce myself, and inquire about the sedges in the triangle bed. He told me that it was Carex bromoides (brome-like sedge) on the lower end and Carex albicans (white-tinged sedge) on the upper end.

The lower section with more Carex bromoides

The upper section with more Carex albicans

Overall, the sedges were in that post flowering stage where they tend to be more yellow in color.

Bold foliage from Heuchera villosa (hairy alumroot) and the vertical spires of Digitalis parviflora (small-flowered foxglove) contrasts well against the sedge groundcover.

SPOROBOLUS MATRIX

After I got home and started parsing through photos, I remembered that one of the patterns I noticed in the plantings was Sporobolus heterolepis (prairie dropseed) commonly used as the groundcover layer for mini-matrix plantings. It was used very heavily in the B beds, but in the A beds there would be little blocks of it. This grass would serve as the groundcover layer while other species rose out of it.

Allium christophii (star of Persia) and Echinacea foliage rises from the matrix of Sporobolus heterolepis (prairie dropseed).

In another section it was mostly Echinacea rising from the grass matrix.

I really liked this combination of the spears of Ornithogalum ponticum ‘Sochii’ (star of Bethlehem) piercing through the clumps of Sporobolus heterolepis, and it left me wondering how I could replicate this with Liatris or another species.

In this space Sporobolus heterolepis served as a groundcover near these Baptisia × ‘Lunar Eclipse’ (wild indigo). The contrast in textures really helps the Baptisia pop.

THE PLANTS OF OUDOLF GARDEN DETROIT

And, I wanted to share a few favorite plants that I enjoyed during my trip to Oudolf Garden Detroit.

This spot was one of my favorites from the visit. Sure the Asclepias tuberosa (orange milkweed) is lit, but the verticals of Dalea purpurea (purple prairie clover) and Veronica (veronica), the Allium orbs, and the rising perennial towers behind made this area so rich.

Another favorite pairing was this cool-colored section that featured Allium caeruleum (blue globe onion), Salvia sylvestris ‘Rhapsody in Blue’ (wood sage), Eryngium × zabelii ‘Big Blue’, and Geranium ‘Rozanne’ (geranium).

This combination of Achillea x ‘Moonshine’ (yarrow) and Allium christophii (star of Persia) was dynamite due to the contrasting colors and strong differences in textures.

Another pairing that I liked was Asclepias tuberosa (orange milkweed) with Stachys monieri ‘Hummelo’ (betony). But…

…Lindsey and I discussed how this Asclepias might have been a happy accident that seeded in.

Another combination that I liked was Achillea filipendulina ‘Parker’s Variety’ (yarrow) with Ornithogalum ponticum ‘Sochii’ (star of Bethlehem). The upright triangular shapes contrasted nicely with the horizontal corymbs.

This spot was quite beautiful with Echinacea pallida ‘Hula Dancer’, Asclepias purpurascens (purple milkweed), and Salvia yangii ‘Little Spire’ (Russian sage).

Here’s another spot where Asclepias purpurascens stood out. It is such an underused plant.

Blocks of Penstemon digitalis (foxglove beardtongue) punctuated the planting with their pearly white flowers.

I’m posting this photo to educate and mean it in no way to detract from the beauty and hard work of the gardeners. It seems they have the same frustration with Eragrostis spectabilis (purple lovegrass) that I do. A section of it had died out. For me I’ve learned that it’s a ruderal and just doesn’t last that long.

One last shot of the beautiful Echinacea pallida ‘Hula Dancer’.