Q: I am in desperate need of advice on controlling the Chameleon plant! Its color is beautiful until it shows its aggressive nature. It came as part of a gift and has taken over my flower bed in short order. We tried conventional herbicides to no avail. What can I do?
A: Chameleon plant ( Houttuynia cordata "Chameleon" ), also called Korean Ivy, is one invasive plant. It surprises me that so many nurseries still sell it when it is so prone to take over the garden. Chameleon plant, along with ribbon grass, gooseneck loosestrife and the pink form of evening primrose should all come with a warning label. Unfortunately, they don't and so you are not alone in your struggle to control a very aggressive grower.
Chameleon plant grows from underground stems that can spread rapidly and are extremely difficult to remove. It is often touted as a terrific groundcover for poorly drained, low lying areas. The small white flowers aren't much too look at, but I think the foliage itself is beautiful; variegated red, green and white. The fragrance of the crushed leaves is not very pleasant (I have known a few gardeners who actually get nauseous when they smell it).
Do not try to dig the plant out. Each piece of root you leave behind will create a new plant, generating more plants and an even bigger root system. Most herbicides, organic and conventional, will only manage to knock it back for a month or so. Repeated applications don't seem to do the trick either.
So, here is what I recommend: If it is in an established perennial bed, this fall carefully dig out all the desired perennials, examining them carefully for pieces of bright white chameleon plant roots, removing any you find and throwing them in the trash. Temporarily heel the perennials into the ground somewhere or pot them up in nursery pots. Then weed wack or mow the chameleon plants as close to the ground as possible. Cover the entire area with overlapping pieces of non-waxed corrugated cardboard topped with several inches of organic matter such as shredded leaves, compost or well-aged manure. Do not till or disturb the soil again.
Come spring, add another layer of cardboard and organic matter then cautiously replant your perennials, being careful to disturb the underlying soil as little as possible. Any baby chameleon plants that should manage to pop up need to be removed immediately to further starve the roots. It's a lot of work, but it is a permanent solution. And, the good news is that this method also will control field bindweed, Canadian thistles and other persistent perennial weeds too.
