Sheila...it is a weed :o) and it takes over the edges of my yard. Anywhere the grass doesn't grow it finds a place to spread. It volunteers in potted plants all the time. I used to pull it out but now that I know RAs use it...I leave it alone for the most part...until it gets too invasive - then it gets yanked out...and I drop the ones I pull out onto the live plants along the fence - that way the caterpillars will crawl over to new leaves. Then I pick it up and toss it in the compost.
~ Cat