For the most part, we worry about diseases during hot, humid periods when temperature, dew point, and moisture create the conditions necessary for fungal diseases like Dollar Spot or Powdery Mildew to proliferate. While Fungicide applications can be used either preventatively or curatively, we like to focus on proper cultural practices to stave off or treat the disease before we use those products.
Winter diseases are no different, especially in areas of your lawn that experience frequent melting and the resulting exposure to the elements. Here, lawns can develop Pink and Gray Snow Mold, a common winter turf disease. Snow molds are present for two primary reasons.
First is that the disease was lying dormant in the thatch all along, waiting for the desired climate and atmospheric conditions to grow. This is referred to as the disease pyramid. When just the right combination of “host” (the desirable grass varieties in your lawn), temperatures, and moisture levels meet, dormant fungi grow rapidly resulting in an outbreak.
The second reason snow mold can develop is if the grass blades are actively growing too much or too fast as winter sets in. This is often a result of fertilizer treatments applied too late in the season or with a formulation that is too high in fast-release nitrogen. Improper applications like this will promote overly aggressive top-growth at a time when the lawn needs to be preparing for winter dormancy. Snow Mold will feed off of the lush, leafy tissue until conditions change and push the disease back into dormancy.
You can never eliminate the chance of Snow Mold entirely, but to give your lawn the best chance you should avoid improper late-fall fertilizer treatments. Mainely Grass Lawn Care programs finish around Halloween and our fall fertilizers are specifically designed for slow-release for exactly this reason. No one knows when winter will hit, so we do our best to make sure lawns have the proper balance of macronutrients in the right formulation at the right times of the year.
If you do have Snow Mold heading into spring, the best thing you can do is to lightly rake out these areas as soon as you can to break up the matting and stimulate turf growth. The nutrients in our spring fertilizers will also help grow-out the disease over the ensuing weeks.
If you take these steps, Snow Mold will most likely be just unsightly for a short period of time and long-term damage is rare. Not raking out the area, or repeated outbreaks of Snow Mold over many years may result in enough dieback to warrant seeding of some kind. Our Technicians will identify any issues they see on your lawn and our Account Managers are happy to talk through any questions or concerns you may have!