DNR names milkweed Wisconsin's Plant of the Year

MARSHFIELD – The Wisconsin Department of Natural Resources (DNR) is declaring milkweed as the Rare Plant Monitoring Program's 2025 Plant of the Year and encourages planting milkweed to help monarch butterflies.

Milkweed is an important plant for monarchs, and when combined with other native plants that bloom throughout the spring and summer, it can support a variety of pollinators.

“Monarch butterflies face several major threats, including habitat loss, pesticides and climate change,” said Jay Watson, DNR insect ecologist. “Planting milkweed can help create habitat for monarchs, other butterflies and bumble bees.”

Monarchs breed in Wisconsin throughout the spring and summer, and they need milkweed to survive. It’s the only plant that monarchs lay their eggs on, and it’s the only food that monarch caterpillars eat. Once a monarch reaches adulthood, it may still use milkweed for nectar, but a variety of native plants that bloom from spring to fall are also important.

In late fall, monarchs migrate south to Mexico, where they overwinter in tight clusters. Each year, scientists estimate monarch populations by how much space they occupy, measured in hectares, while overwintering. While 2024-25 numbers found 1.79 hectares up from .99 hectares the prior season, both are part of a decades-long decline in their population.

The Rare Plant Monitoring Program is a group of trained volunteers who work with the DNR to locate, record and update the presence of rare plants throughout the state. The plant of the year becomes a focus for volunteers who can request rare milkweed surveys and contribute to a statewide status update on these species.

Of the 13 native milkweed varieties in Wisconsin, five are listed as endangered, threatened or special concern. Showy milkweed is the state's only nonnative milkweed.