by North Forty News Staff | NorthFortyNews.com
Snow mold may appear as patchy grass across Northern Colorado lawns after extended winter snow cover
Northern Colorado’s unpredictable winter weather can create unexpected challenges for homeowners as spring arrives. When snow lingers on lawns for long periods, it can set the stage for snow mold—an uncommon but occasionally damaging turf disease that becomes visible once the snow melts.
Snow mold is caused by cold-weather fungi that develop beneath extended snow cover, especially when grass is left long or covered with fallen leaves and debris. While Colorado’s dry climate typically limits fungal issues, prolonged moisture trapped under snow can create the right conditions for mold to form.
There are two main types of snow mold that may appear in spring. Gray snow mold, also known as Typhula blight, leaves grayish-white circular patches of matted grass and usually affects only the grass blades. Pink snow mold, also called Microdochium patch, appears whitish to pink and can be more severe, potentially damaging grass crowns and roots. Both types become noticeable as the snow recedes, often leaving crusty or flattened areas across the lawn.
Snow mold is more likely to develop in lawns with excessive thatch, heavy leaf cover, or tall grass going into winter. Late-season snowstorms and repeated freeze-thaw cycles can further increase risk by keeping turf wet and shaded for extended periods.
Prevention starts well before winter arrives. Clearing leaves and debris from turf areas in the fall reduces moisture retention under snow. A slightly shorter final mow of the season can also help prevent grass from matting down. In areas where snow mold has occurred repeatedly, some homeowners choose to apply a preventive fungicide in the fall, though many lawns can avoid problems with proper maintenance alone.
If snow mold appears in spring, recovery is often straightforward. Lightly raking affected areas helps restore airflow, remove debris, and encourage drying. As temperatures rise, sunlight and Colorado’s naturally dry air work against the fungus. In many cases, grass recovers on its own. Where turf has died, reseeding with a matching grass variety can help restore damaged patches.
Snow mold may look alarming at first glance, but with timely care and good seasonal practices, most Northern Colorado lawns recover quickly as spring conditions improve.
Make North Forty News part of your morning. Get Northern Colorado’s top stories, weather, and events every day at 5 a.m. in our Daily Update.
https://northfortynews.com/dailyupdate
Source: Lawn care and horticulture guidance adapted from regional extension and turf management best practices.
