Snow mold is one of the most common spring lawn issues in Minnesota and Wisconsin. It shows up right after the snow melts and leaves the lawn looking matted, patchy, and discolored. The good news is that most lawns slowly recover as we move through the spring. With the right care you can also greatly reduce the chance of seeing it.
Why Snow Mold Is Common in Minnesota
Our region has long, cold winters with heavy and extended snow cover. Snow mold fungi thrive in cool, moist, and shaded conditions, which describes the environment under deep snow perfectly. When snow arrives before the ground is fully frozen or stays on the lawn for long stretches of time, the grass remains damp and protected from sunlight. These are ideal conditions for the fungus to grow.
Years with early snow, lots of snow, or a long lasting blanket of snow tend to produce the most snow mold.
What Snow Mold Does to Your Lawn
Snow mold affects the grass blades first. The fungus bleaches and kills the blades, leaving circular patches of straw colored or gray turf in early spring. There are two types of snow mold:
- Pink snow mold produces a pink or salmon colored tone. Pink snow mold causes the most long term damage as it can affect the crown in extreme infections.
- Gray snow mold produces a gray webbing or fuzzy growth. Grey snow mold almost never causes long term damage as it only infects the grass blade.
Why One Lawn Gets Snow Mold and Another Does Not
Several factors influence whether a lawn develops snow mold.
- History of the disease : The fungus overwinters in soil and plant debris. A lawn with previous snow mold carries more fungal material, so it is more likely to get it again.
- Grass species and variety: Some varieties have greater natural resistance. Even two lawns with the same general species can behave differently based on variety.
- Maintenance practices: A lawn with longer grass, heavy leaf cover, thick thatch, low areas, or compacted areas is more prone to infection. Large snow piles or shaded areas where snow lingers also increase risk.
How to Prevent Snow Mold
Prevention works best when started in the fall. Here are the practices that help the most.
- Keep mowing into late fall: A final short cut (2-3 inches), without scalping, reduces matting and keeps moisture from getting trapped at the surface.
- Remove leaves and debris: A clean surface gives the fungus fewer places to survive.
- Improve drainage and airflow: Spread out plowed snow rather than piling it high. Try to reduce large drifts along driveways or shaded structures.
- Consider a fall fungicide: For lawns with a history of snow mold, a properly timed late fall fungicide can greatly reduce the chance of infection. It must be applied before consistent snow cover arrives, since the fungus begins its activity under the snow where treatments cannot reach. This is something bioLawn can apply.
Researchers at the University of Minnesota and partners around the world are actively studying winter turf diseases. Their work continues to shape the best strategies for homeowners in our region. Learn more by visiting their website.
What To Do If You Already Have Snow Mold
If you see snow mold in early spring, do not worry. Most lawns recover with simple steps.
- Let the lawn dry: Wait until the soil firms up before working on the area.
- Gently rake the patches: This stands the grass back up, removes dead material, and improves airflow and sunlight exposure.
- Give it time: Warmer temperatures and normal spring growth will bring the lawn back.
- Overseed if needed: If an area looks thin after recovery, overseeding can fill it in and introduce new varieties that are less susceptible.
A Simple Way to Keep Your Lawn Healthy
Snow mold can feel mysterious because it happens out of sight all winter, but it is manageable with the right approach. If you want help preventing snow mold or getting your lawn growing again in spring, our team is ready to assist. We use environmentally responsible treatments tailored to Minnesota and Wisconsin conditions so your yard can stay healthy all season. Let us know how we can support you.