Thanks for writing. Without being able to see a picture of the plants, I'm sorry to say I can't say what they are. However, if they're common in your area, the staff at your local garden center or nursery should know what they are --- I'd start there. Otherwise, you can take a picture of one and post it on our Web site at http://www.bhg.com/photos/gardening/ --- let me know the URL and we should be able to help after seeing it.
---Justin, Senior Garden Editor, BHG.com