My second example is Creeping Charlie, Glechoma hederacea. This plant was also introduced as an ornamental ground cover and has a long history of being used for medicinal purposes. This is the plant that we all, now love to hate. This plant has also been naturalized but is also invasive.
So let’s clarify the term invasive. What makes a plant invasive? According to Mr. Galen Gates, a horticulturist and botanist, who I had the pleasure studying under at College of DuPage, stated, “a plant that upsets by dominating an area is considered invasive.” If you introduce a new species to a setting, and it spreads and damages the surrounding ecosystem, this is invasive. In the case of Lilacs and Forsythia, they behaved themselves after their formal introductions in the 18th century. Creeping Charlie became the wild child of ornamentals, which still has folks scratching their heads wondering why it was introduced in the first place. The examples I used of Lilacs / Forsythia and Creeping Charlie have become naturalized, but creeping Charlie has become invasive. Creeping Charlie grows aggressively in places people do not want it and disturbs the ecology with its invasive growth patterns, becoming a weed.
Try planting a native Illinois plant or two this spring and see what happens. When thinking about plants for your garden this growing season, don’t just pick one because it looks good at the store. Pick a plant that has a job and works with your sustainable beliefs. You don’t have to tear out everything to “go native.” Just make sure that you have the right plants in the right place and you know that there is a purpose to your plantings. In Brookfield Illinois, I look forward to the palette of yellow and lavender that Forsythias and Lilac shrubs share with us, after a long winter sleep. These colors remind us that warmer days are ahead and new growth will flourish. This growth is not just in your outside garden, but in your garden knowledge as well.