Your lawn looked great heading out of fall – lush, green, and spot-free. Then the snow came, thick and white and cold, and when the piles melted in the spring, to your shock you found your once-immaculate lawn was spotted with decaying yellowish circles.
Snow mold. Blech.
Snow mold occurs most frequently when the first snow of the year falls wet and heavy and the ground underneath doesn't have a chance to freeze properly. The excessive and relentless snow hammering much of America in the winter of 2011 could make snow mold a major problem in the spring.
Fortunately, while the appearance of snow mold can be disheartening, the blight is relatively easy to eradicate. The bad news is you'll have to watch your lawn get worse before you can help it get better.
Snow mold first appears when the snow begins to melt, and the unsightly patches will continue to grow for as long as the grass is cold and wet. The circles can grow several feet in diameter and become coated with a thin coating of gray or pink mold, depending on the strain. The key to eliminating snow mold lies in waiting for the grass to dry completely.
Waiting while your lawn suffers may be difficult, but you need to do it – the lawn has to be dry before you can start to deal with the mold. You don't have to stand by idly. Shoveling and wind drifts create large snow piles in a yard, snow piles that melt slowly and prolong the drying period. Dispersing the snow evenly helps to speed up the drying process throughout the yard.
Head outside with a rake and a trash bag after the lawn dries. Rake the infected areas to remove the dead grass and mold. Avoid raking mold into mold-free areas and dispose of the diseased grass in a trash bag – DO NOT try to compost it.
Once the moldy grass is gone, rinse the rake to wash off any spores stuck to the tool. Rake the lawn vigorously to pull up the layer of thatch built up between the grass and the surface of the soil. Snow mold spores settle into the thatch layer and the fungus can return with a vengeance the following winter if you don't remove it. Trash the thatch the same way you did the dead grass.
Applying a snow mold fungicide doesn't help in the spring, so don't waste your money on the product. The chemical works to prevent new growth overwinter rather than eradicate existing infestations.
If the snow mold got a good hold on your lawn, all the raking can leave behind big patches of bare soil. There's not much you can do about it other than re-seed or re-sod the area to keep weeds from moving in.
Only one step remains once the lawn is raked, dethatched and mold-free; preventing the invader's return. While we can't do anything to change weather patterns – not yet, anyways – you can make your yard as uninviting to mold as possible. Applying a half-strength dose of fertilizer in the late fall or early winter keeps the lawn healthy, and cutting the grass low for the cold months provides less surface area for the mold to take root on. Early winter's when you want to spread that expensive snow mold fungicide, too.
Eradicating snow mold takes no more than a weekend, maybe even an afternoon. Don't let the fungus frustrate you – it's more of a temporary annoyance than a lasting problem.
