It seems that plants are always teaching me new lessons about how they behave in the garden and respond to weather and other conditions. This summer, there are three native plants that have been on my mind.
First, Yellow Coneflower (Ratibida pinnata). I’m fond of this plant with its central cone like a clown’s nose and bright yellow yet droopy ray flowers. In rich garden soil, though, it tends to grow too tall (5′ or more) and flop. To limit this tendency I use tall tomato cages.
This year it’s growing even taller than usual – over 6′. It must like this year’s hot summer, despite the lack of rain (though I have done some occasional watering). My takeaway: I really need to cut this plant back in late spring. I’ve been told that you can also cut it back in late summer after it blooms and you’ll get another round of flowers. I’ll try that.
Also, it’s starting to self-sow pretty aggressively, which for some reason it didn’t seem to do for the first few years. Now it’s popping up a fair amount, so I think I’ll have to start editing it out. I suspect Yellow Coneflower performs better in a leaner soil and with more competition.
Next up: Hoary Vervain (Verbena stricta). This is another plant I like a lot, though I object to the name. Sounds like a character from Lord of the Rings. “To find the Ring, you must first seek out the Hoary Vervain.”
So here’s what I’ve learned about Hoary Vervain. First off, it will self-sow. A lot. BUT it will not compete with taller plants. Which means that in the Driveway Border, it self sows only along the edge, which is supposed to be covered with various low, mounding plants. Plants so often refuse to cooperate with my design ideas.
Hoary Vervain is normally upright but here it is leaning at a distinct angle, I suspect to get away from the tall plants that are blocking the morning sun. They do get full afternoon sun. Or it could be the rich soil that causes it to grow extra tall and lean. (Though I don’t fertilize this border but only allow the plant debris to decompose.) The Hoary Vervain also, I suspect, would be performing better if they had been cut back in May.
I will say, though, that the Hoary Vervain seems unbothered by this summer’s heat and dryness.
Finally, Aromatic Aster (Symphyotrichum oblongifolium – the botanical name is a real mouthful!). This plant is at the far end of the Driveway Border, facing west. My idea is that it would provide a low mound of blue blooms in fall. And it has, although it tends to grow bigger than I expected.
Aromatic Aster likes full sun and drier soils but this year it is showing signs of stress, with some stems turning brown. These I have tried to prune out. The heat of the afternoon sun is intensified by the pavers in our driveway. My lesson learned, which I guess sounds pretty obvious, is that Aromatic Aster can suffer in just moderate drought if it sits in a challenging microclimate. In these circumstances it needs supplemental watering to look good.
These days it’s hard not to look at the garden and think how I would have done things differently if I knew then what I know now. Certainly, rich soil can be a mixed blessing, unless you are growing food crops. Though I have always loved tall plants, and that has not changed. Gardeners must live and learn, because we are working with living things that react to their environment in dynamic ways. But that is part of the fun.