Fight Garlic Mustard with Native Groundcovers
Garlic Mustard (Alliaria petiolata), Buckthorn (Rhamnus cathartica), and Japanese Honeysuckle (Lonicera japonica). If plants could ride horses, these would be the three horsemen of the Invasive Plant Apocalypse – at least for shady areas in the Midwest. However, a recent post in The Native Plant Herald (the blog of Prairie Nursery in Wisconsin) tells us how native woodland groundcovers can be used to keep these botanical barbarians from running amok. To read the post, click here.
To be clear: the plants discussed here are generally native to parts of the eastern and central regions of the US and Canada. In other regions, this information may not apply.
I have experience with some of the plants discussed in the post. Wild Ginger (Asarum canadense), for example. According to Prairie Nursery, Wild Ginger “forms a solid mat of roots at the soil surface … Once established, a bed of Wild Ginger is essentially impervious to invasion by garlic mustard, buckthorn and honeysuckle.”
I can attest to the solid mat of roots. What’s more, Wild Ginger is a darn good-looking groundcover for shady gardens. On the west side of our house, I have a couple of patches of Wild Ginger, in some places interplanted with Lady Fern (Athyrium filix-femina). They seem to live comfortably together. Wild Ginger roots do smell like ginger, but the plant is entirely unrelated to culinary ginger.
Unfortunately, to establish a bed of Wild Ginger you first have to remove the Garlic Mustard.
Another native recommended in this post is Long Beaked Sedge (Carex sprengelii). I planted a patch just last year in our shady back garden and it has already formed a very solid mass.
Long Beaked Sedge has pretty nice seedheads.
There’s a lot of Northern Sea Oats (Chasmanthium latifolium) in our garden. It definitely forms a solid mass, and it’s a really beautiful grass in summer and fall.
However, be careful where you put it, because it is a bear to remove and has definite expansionist tendencies.
There’s one plant mentioned in this post that in my garden has not been much of a weed inhibitor: Big Leaf Aster (Eurybia macrophylla). Or as my kids like to call it, Big Ass Leafter. Not sure if I don’t have the right conditions, or what.
Anyway, this post mentions a couple of other plants and I’d recommend it to anyone who has a shady or woodland garden.