Certain ornamental plants have the bad habit of wandering around where they may not be wanted.  Just like a weed, an invasive plant is one that is growing unfettered in the wrong place, at least in the opinion of the gardener.

Fortunately, there are not a ton of truly invasive plants that we routinely find in our beds and borders. There is another group of plants that fall into a "debatable" class when it comes to invasiveness in the home landscape. If you talk to enough gardeners, some will call them invasive while others feel that are just nice groundcovers and not a problem at all.

Included in this group would be such plants as bugleweed (Ajuga), gooseneck loosestrife (Lysimachia clethroides) dead nettle (Lamium) and sweet woodruff (Galium odorata). Left untended, these plants will move around in the garden but a little thinning out in the spring will often keep them in line.

Again, this does not mean that you should never grow any of these groundcover/invasive plants. It does mean that you should be aware of the potential problem BEFORE you plant them. Many of the invasive types are extremely difficult to get rid of once they become established especially when they are mixed in amongst your desirable trees, shrubs and perennials. Also, they could creep over into your neighbor’s landscape if not kept under control.