I always like to diversify my native plants as much as possible, and even though I try to research each species ahead of time, some of them always come back to bite me. Here is my list of regrets. If anyone has had a different experience with these plants or has found a way to deal with them, please post a response. Also to help out the rest of us, please consider posting your own list.
Here is my list from worst to “least worst”:
Virginia Wild Rye (Elymus virginicus)
1. Virginia Wild Rye (Elymus virginicus). I can’t find a single good thing to say about this plant except that it is a cheap and very easy-to-grow grass. Since it is a cool season grass, it dries to a crispy brown in Tennessee’s summer heat and looks like a farmer’s field ready for harvest. It can’t stand up by itself in a storm and takes everything around it down with it when it goes. It is listed as “short-lived” but that is inaccurate. I have been pulling and dead-heading it for five years.
2. Big Bluestem (Andropogon gerardii). Generally, this is considered a very desirable meadow grass. Tall at 6-7’, it is sturdy and generally stands straight even after a storm. But it RE-SEEDS to the point of taking over and driving out everything else in just about 3 years. I complained to my seed source, but I don’t think they believed me, saying only that they had never heard of such a thing. I did buy my seeds from a northern state, so maybe I got a northern “ecotype” of the plant that just goes nuts in Tennessee’s warm climate. What are other people’s experiences with this plant and where did you get your seed?
3. Wild Strawberry (Fragaria virginiana). Although it is a charming, attractive groundcover, its ability to spread puts Bermuda grass to shame, especially if planted in sun. It works fairly well in dry shade, but it is almost like something from outer space if put in full sun with plenty of water. It is often on rain garden plant lists, and I made the mistake of using it in my rain garden. In less than 3 months, a total of 6 plants had buried every other plant in the garden, and when I pulled it all out, I had rooted plants about every inch to half inch.
Wild Petunia (Ruellia humilis)
4. Wild Petunia (Ruellia humilis). This plant is a darling, small purple petunia that makes a great groundcover. I read that it shoots its seed up to 10 feet through the air, which at the time sounded rather charming. In reality, it is a huge headache if you have any areas within 10-15 feet where you don’t want it or if it is planted among less aggressive plants. Since it blooms the first year from seed, those plants will then send their seed out another 10 feet..…kind of an exponential explosion. Even though it is a small plant, you cannot hand pull it by the roots . I am no longer sure that I want it, but it is too late. Once planted, it is so invasive that it is here to stay.
Sweet Black-Eyed Susan (Rudbeckia subtomentosa)
5. Sweet Black-Eyed Susan (Rudbeckia subtomentosa). This plant is both pretty and a huge headache. It is a great rain garden plant with bright yellow flowers. However, it is a giant plant at 5-6’ that sprawls in all directions by mid-summer, burying everything around it. It re-seeds with abandon, popping up everywhere in the yard. If you don’t have too many, the only solution is to cut it back to at least half its height in early June, which turns it into a somewhat manageable bush by the time it blooms in late July.