What is Snow Mold? What should I do about it?

When our Minnesota yards reappear when their winter covering of snow melts in the spring, we don't always like everything that we see. The flattened, dead-looking grass may not just be bent over with the weight of a winter's worth of snow. Your lawn may be showing signs of fungal Snow Mold diseases.

What is Snow Mold?

Snow Molds can grow during any winter but they can be especially severe when early snowfall covers wet, unfrozen ground. Leaf and lawn debris left on the turf will also make your lawn more susceptible to fungal diseases.

Fungicide treatments are not normally needed to treat these diseases except in the most severe cases. On lawns that have been maintained with adequate fertility and proper mowing, the roots and crown of the grass plants should allow regrowth in the spring.

Should I rake my lawn in the spring?

If you thought that your lawn looks like it needs raking after being flattened by snow and stressed by Snow Mold, you're right! Be sure that you rake gently though, and don't rake unless the turf is dry, both on top and under those matted areas. Power raking is not recommended unless you have a severe thatch problem.

If you had little critters tunneling under the snow in your yard over the winter, rake those areas as well, to pull up the dead material. Voles and mice, like Snow Mold, do not usually damage the crown or roots of the turf. After you have raked, give the damaged areas some time to recover.