March is four months away so you’re probably wondering why we’re talking about Snow Mold now. Snow Mold is one of the most common late winter/early spring lawn diseases in the northeast. Preventing Snow Mold means that landscapers and homeowners need to take action now. You may not notice Snow Mold until the snow on your lawn melts. Snow Mold is recognizable by two colors, pink and grey. Pink Snow Mold can grow up to 8 inches in diameter while the Grey Snow Mold can grow to several feet across. These patches can also be covered in a web-like material called Mycelia. Preventing Snow Mold can be done with the use of fungicides and soil amendments and by using the tips listed below.
Mow before the first significant snow
Longer grass dramatically increases the chance that Snow Mold will grow. This is especially true for Grey Snow Mold. When you do the last mow, you’ll want to cut the lawn an inch to an inch and a half shorter than normal. Just be sure not to scalp the grass.
Apply a preventative fungicide
Apply a lawn fungicide after the last mow of the season and before the first heavy snow is set to hit. Even if it is a low snow season, taking preventative steps like applying fungicide will lessen the chance that the Snow Mold shows up. It also acts as a barrier to freeze-tolerant Snow Mold.
Dethatch the lawn
Lawns that have a thick layer of thatch are more prone to Snow Mold. You should start dethatching in early fall and continue through late fall. Raking should continue until the thatch is less than three-quarters of an inch thick. There are specialty metal rakes designed for thatching which are usually the best to use.
Fill in spots that are prone to drainage
Snow Mold grows in moist areas so you’ll want to find all the spots on the lawn where water pools before the first big snow. A layer of topsoil will usually do the trick or consider having some drainage work done before winter.
Rake up the last of the leaves
Decomposing leaves create a great environment for Snow Mold to grow in. All of the leaves that have fallen should be raked up and disposed of. You’ll also want to be sure not to leave any leaf piles on the lawn over the winter.
Don’t let the snow pile up
Snow that sits in large piles for extended amounts of time takes longer to melt. Deep snow that is still around when the weather warms is an ideal place for the Snow Mold to start growing. When clearing sidewalks and driveways, try to evenly distribute the snow as opposed to leaving it in one large pile.