Landscaping Alternatives for Common Invasive Wetland and Aquatic Plants

Authors: Wisconsin Department of Natural Resources, Minnesota Department of Natural Resources, University of Wisconsin Division of Extension, Extension Lakes University of Wisconsin-Stevens Point College of Natural Resources

Why Alternatives?

Aquatic and wetland plants are great additions to your water gardens, ponds, and rain gardens to oxygenate the water, shelter and feed wildlife, provide beauty, and support pollinators. The plants we choose for rain gardens are also key to how it will function to reduce runoff. Over time, we have learned that many invasive plants introduced to our gardens impact native species by spreading into natural areas. This publication suggests these alternatives because they:

• Share desired ornamental and environmental features.
• Grow in the Upper Midwest successfully.
• Are available from nurseries and garden centers.
• Will be unlikely to escape from cultivation or cause harm.

A beautiful garden and yard for a healthy environment

Gardeners have many goals in mind when they choose their plants: beauty, structure and design, water quality, attracting birds, and more. Some plants used in backyard ponds and rain gardens are considered aquatic invasive species (AIS). AIS can outcompete native plants, fish, and animals for food, shelter, or habitat if they spread into natural lakes and rivers. AIS can interfere with fishing, swimming, and boating. They cost millions of dollars annually to manage and millions more in lost revenue for businesses, natural resources, and recreation. By choosing wisely for our landscapes, we reduce the risk of these species causing harm.

Why use native plants?

Although we can safely have many non-native plants in our gardens, native plants which evolved with the area’s birds, insects, and other wildlife will provide the best shelter and food. You can make your garden an ecological oasis for them. Native plants can be just as attractive, and are likely hardier, than non-native plants.
Sources for native plants, as well as cultivars of those plants, include garden centers, specialty growers, and landscapers. Many states have growers that specialize in their native plants as well as seeds. Be careful of sources found online. Although selling plants to people in states where they are listed as invasive is usually illegal without permits, some sellers operate without knowing or without being concerned about the laws.
Visit Wisconsin DNR at dnr.wi.gov and search:

• Wisconsin Native Plant Nurseries
• Wisconsin Restoration Contractors

Visit Minnesota DNR at dnr.state.mn.us and search:

• Native plant suppliers, landscapers, and restoration consultants

What are invasive plants?

Invasive plants are non-native plants that cause economic or environmental harm or harm to human health. Midwest states have somewhat different regulations regarding invasive species. For more information on invasive species and regulations in your state, check with your state’s natural resources agency.

Tips for invasive-free gardens

• There are many books and online resources (see below) that can help you find safe, non-regulated plants that can fill the same functions of color and structure for your garden.
• Avoid plants described as “spreads easily” or “fills in quickly.”
• Never dump yard waste into natural waters or landscapes. Options for disposal can vary by state and locality. In Wisconsin, put invasive plants into garbage bags and label them “Invasive-Approved for Landfill by WDNR.” In Minnesota, search
“noxious weed disposal” on the Department of Agriculture’s website.
• Home composting may not destroy all reproductive parts. Monitor areas where compost is spread for unintended plant growth.
• Check purchases for unexpected hitchhikers such as snails, crayfish, plant fragments, seeds, etc.
• Please don’t share plants. Sharing plants with friends and family has resulted in the accidental spread of many hidden invasive species, including jumping worms (Amynthas species).
• Collecting wild plants is often illegal and risks damaging native habitat.

Floating and Emergent Plants

Wetland Grasses and Grass-Like Plants

Shady Area Plants

Short and Medium Height Plants

Tall and Showy Plants

Additional Resources:

View Invasive Species from the Wisconsin DNR or Invasive Species from the Minnesota DNR

Report an invasive species by emailing Invasive.species@Wisconsin.gov

Check out the Technical Guidance (Native Planting Companion) and Guide to Native Plants at healthylakeswi.com

Minnesota Native Plant Guide

Missouri Botanical Garden Plant Finder

Think you’ve found a new invasive species or are having trouble with one on your property?
Check your DNR invasive species pages for identification, status, and how to report.

Acknowledgement:
Lauren Mortensen for general support and web editing.
All photos by Patrick Goggin unless otherwise noted.
CC = Creative Commons link to license