There is an ever-changing group of plants appearing in and about our gardens which deserve attention. These plants have the potential to cause ecological disturbances because they monopolize nature's resources. Many are quite familiar to us and sometimes even occupy space within our gardens. Some of the most insideous might even have been sold to us by reputable nurseries. The problem is that these plants compete for sunlight, water, nutrients and space and in so doing they can threaten other species. They often produce large numbers of viable seed each season or spread rapidly via aggressive root systems.
Horticultural literature abounds with synonyms: invasives, exotics, aliens, noxious, obnoxious, aggressive, non-native, or progressively quick growers. No matter what label we choose, it is more important that we recognize the presence of these competitive additions to our gardens, our properties, parks, public lands and waterways. Here at Vermont Flower Farm we are beginning to do a better job recognizing plants that are successfully overpopulating themselves in our area. Our goal in mentioning "problem plants" is to broaden your awareness and concern.
Watch for purple loosestrife, common buckthorn, Japanese barberries and honeysuckle, garlic mustard, Oriental bittersweet, wild parsnip, Japanese knotweed, giant hogweed, thistle, burdock, field bindweed, eupatoriums, angelicas, and goutweed. Within your gardens, use care with the mallows, tradescantias, artemisias, perennial foxgloves, sweet cicely, and gooseneck loosestrife. Planting one plant is easy but eradicating a plant-gone-wild is often difficult.
For more information on invasives, begin your search with a very good overview prepared by the New England Wild Flower Society. Try to remember the society's statement on invasives:
"Invasive plant species are among the greatest threats to the integrity of natural areas."
From top left: Angelica, bittersweet, burdock, Clematis tangutica, coltsfoot, gooseneck loosestrife, Joe Pye weed, sweet cicely, wild parsnip