Invasive and Aggressive Garden Plants

Not all garden plants behave themselves. If not handled properly, their bad growth habits can quickly get out of control. While that beautiful plant may have captured your eye, it's important to take note of its growing characteristics before planting it in the garden. Beware of plants labeled as rampant growers, fast spreading, noxious, prolific, vigorous, creeping, robust, or naturalizing. These are all red flags to possible garden bullies that may likely take over your otherwise well-behaved garden.

An important note to keep in mind is that not all of these bullies are created equal. Some plants may be very aggressive, freely growing in areas where we would rather they not while others are more invasive and can actually over run or take over garden areas. Aggressive garden plants can usually be tamed by planting them in containers or bottomless pots. Good examples include members of the mint (Mentha) family, English ivy (Hedera helix), periwinkle (Vinca minor), mullein (Verbascum thapsus), and various bamboo species.

Invasive garden plants, on the other hand, are much more difficult to contain and control. In some cases, these plants actually require total removal in order to eradicate their invading growth. Some common plants that fall into this category include lily-of-the-valley (Convallaria majalis), bugle plant or ajuga (Ajuga reptans), Peruvian lily (Alstromaria aurea), and various violet (Viola) species.

Even though a plant may be deemed aggressive or invasive, its actual growing behavior depends on the region in which it's grown as well as the soil, light exposure, and moisture levels. For example, many people find that ajuga species can be quite aggressive or even invasive in the garden. While they certainly grow and spread quickly, making excellent ground cover plants, I have not found them to be too intrusive in my garden. Of course, I also keep them in an area where they receive quite a bit of sun, which may inhibit some of their growing characteristics.

The next time an interesting plant catches your eye, pay careful attention to its growth habit. Recognizing particular red flags can help determine whether a plant is a good candidate for your garden. But don't be alarmed if you find something that may have aggressive tendencies. In all likelihood you can still enjoy the plant by growing it in a container instead or simply place it in an area where its vigorous growth will not become a factor.