I have several species of aster, all but one of which (
Silky Aster (Symphyotrichum sericeum)), have proven to be too mobile for their own good. Planting
Common Blue Wood Aster (Symphyotrichum cordifolium) was one of the worst gardening mistakes I've ever made.
Wild Petunia (Ruellia humilis) proved to be a surprisingly difficult plant to deal with. It's a fairly uncommon plant around here, only see it in well managed native pastures. However, within less than four years of planting it in one flower bed, it had become a dandelion-type weed throughout my lawn. At certain times of the year, the lawn almost turns purple from all the Ruellia blooms. Doesn't bother me much, but it's sort of horrifying to some of the neighbors.
I knew from previous experience that most species of goldenrod were too aggressive for small gardens, but talked myself into trying
Elm-leaved Goldenrod (Solidago ulmifolia) in a very dry portion of a woodland wildflower garden where I'd had difficulty keeping other plants alive. It was actually quite lovely, until it exploded across the whole bed. Planted
Windflower (Anemonastrum canadense) in the same area for the same reason and got similar results, although it appears the goldenrod is going to "fix" that particular problem in the end.
I had successfully grown a couple of species of Eutrochium in prairie gardens over the years and thought I'd try
Joe Pye Weed (Eutrochium purpureum) in the woodland wildflower bed. Turned out to not be the best decision. It's much harder to contain than the prairie species and isn't nearly as pretty, either.
A botanist friend convinced me to grow
Prairie Milkweed (Asclepias sullivantii), claiming that it is much better behaved than either Common or Showy Milkweed. It's not.....
Compass Plant (Silphium laciniatum) and
Prairie Dock (Silphium terebinthinaceum) are somewhat aggressive in terms of seeding themselves around, but the real problem is they are just too big in proportion to the space I have.
Blue Wild Indigo (Baptisia australis var. minor), one of my all time favorite plants, is also surprisingly boisterous at producing seedlings in places I'd rather they not be.
That all probably sounds pretty bad, but the vast majority of native species I've tried have turned out to be wonderful garden plants. The big knock on native plants is that many have very short bloom times compared to traditional garden plants. That's part of the reason I grow so many species, a particular plant may only bloom for a short time, but something is in bloom out there every day from late March through early November
