“What was that?” I pondered as a ground-hugging lavender haze caught my eye driving down the road last spring. What once was a forest had been clear cut the previous summer, and a scraggly grassland had begun to cover up the sins on the site. The flowers appeared in the gaps between tan broomsedge.
Glandularia canadensis (rose vervain) from the air
The next time by, I slowed down, and I recognized the plant even from 100 feet away. It was Glandularia canadensis (rose vervain), a plant I had in my own garden. But, these patches were huge. The removal of the trees had opened up enough light for it to thrive and now bloom. Who knows how many years the plants had skimped by in the shade slowly spreading until disturbance opened up the sky.
I flew my drone up to snap some pictures of the hillside over the eight-foot deer fence. Further away from the road was an even larger patch back along the tree line. It was a treat to see just how abundantly this plant could grow in the wild. I’ve had it in my garden for a few years now as small clumps where competition kept it in check. Let go on this hillside it had filled in quite well.
More lavender haze of Glandularia canadensis
I would rank Glandularia canadensis here in east Texas as mostly ruderal with a dash of competitor. They are very short lived in my garden and like to ramble around and through plants. This member of the verbena family shows the pattern of horizontal perenniality, depleting the resources at its center and then dying out as new growth threads itself through the bed to find open spots to seek out new nutrients.
Glandularia canadensis here at Ephemera Farm
Interestingly, the Glandularia genus exhibits what’s called amphitropical distribution, where a species grows in the temperate zones of North and South America, but not in the tropics in between. Genetic studies hypothesize it originated in South America before spreading north.
Rose vervain is one of my first natives to begin flowering in the beds and starts in some years in late February. I’ve watched the earliest swallowtails flit above the flowers. The bloom color combines well with Phlox pilosa. It’s almost a perfect color echo, the vervain being ever so slightly more purple as it fades from bloom and the phlox being ever so slightly more pink as it is just beginning to flower.
The color echo between Glandularia canadensis and Phlox pilosa
My wild type plants finish flowering in spring, but other selections flower longer into the year. ‘Homestead Purple’, a purple variety that was found on a homestead in Georgia, is probably the best known cultivar.
And, over the past year, I have gotten to know ‘Kathy’s Kandy’ well, an introduction from my friend and mentor Carol Reese of Tennessee. Her friend Kathy found it growing in a horse pasture and said that it flowered 10 months out of the year. For us in Texas, that’s true, too, minus the warmest and coldest parts of the year.
Glandularia canadensis ‘Homestead Purple’ make a nice foil for the massive flowers of Oenothera macrocarpa.
The ever-so-slightly semi-double flowers of Glandularia canadensis ‘Kathy’s Kandy’
This year, there are less flowers on the hillside. The grassland has grown wilder and woolier, and pines have been replanted on the site, but I still see hints of lavender in the underbrush. Glandularia canadensis is a survivor in the wild and in my garden, and whether you welcome the species or cultivated forms of rose vervain into your plantings, I know you’ll enjoy watching this spring perennial hop from spot to spot through your beds.