Originally planted as a garden ornamental, Japanese barberry can quickly escape cultivation and invade Wisconsin’s woodlands. / Photo Credit: Wisconsin DNR

By Erika Segerson-Mueller, DNR Invasive Plant Program Specialist, Oshkosh;
Erika.SegersonMueller@wisconsin.gov or 715-492-0391

While winter is just beginning to creep in on Wisconsin, many gardeners are already thinking ahead to the next spring planting season. While dreaming of spring blooms and designing your next garden or landscape layout, consider invasive plants that may try to weed their way into your plans.

Many invasive plants that are problematic for Wisconsin forests started as garden ornamentals. Although Wisconsin regulates 145 plants under the invasive species rule NR 40 prohibiting their sale, it’s essential to check your selections before purchasing and choose native plants when possible.

Wildflower seed mixes can be especially problematic in hiding invasive plants. Seeds for invasive plant species may be mixed with native wildflowers in seed packs, so carefully read the label before buying. There are other non-native plants available that do not pose the threat of becoming invasive. If you aren’t sure if a plant is invasive, try searching the name along with “invasive” and “Wisconsin” to verify.

Invasive plants can quickly spread and take over an area, crowding out other plants and creating a monoculture (an area dominated by a single plant). This can reduce biodiversity and increase fire risk. Native plants are adapted to the local climate and soil and will attract beneficial insects and pollinators.

A list of Wisconsin native plant nurseries is available to help you find your closest option for native plants and seeds.

The Midwest Invasive Plant Network offers a detailed brochure for gardeners and landscapers with a list of invasive plants to avoid and suitable alternatives for those invasives. They have also created a free mobile app that is available for download.