Snow mold is a common lawn issue that appears as matted, discolored patches of grass in early spring. It’s a fungal disease that thrives under prolonged snow cover, particularly when heavy snow accumulates on unfrozen ground. While snow mold can look alarming, the good news is that it rarely kills your grass—it simply weakens it temporarily.

What Causes Snow Mold?

Snow mold occurs when moisture and cool temperatures create an ideal environment for fungal growth. Several factors can increase the likelihood of snow mold development, including:

• Extended Snow Cover: Thick layers of snow that sit on the lawn for months prevent air circulation and create damp conditions ideal for fungal growth.

• Heavy Thatch Layers: Excess thatch traps moisture, providing a perfect environment for snow mold to develop.

• High Nitrogen Fertilization in Late Fall: Over-fertilizing before winter encourages excessive blade growth, which remains vulnerable to fungal infections.

• Poor Lawn Maintenance Before Winter: Leaving behind long grass, leaves, or other debris can increase the risk of snow mold forming under the snow.

Types of Snow Mold

There are two main types of snow mold:

• Gray Snow Mold (Typhula blight): Forms light gray patches and is less damaging to lawns. It survives in infected plant material but does not harm the roots.

• Pink Snow Mold (Microdochium patch): More aggressive and can affect the crown of the grass, making recovery more difficult.

How to Treat Snow Mold

If you spot snow mold in early spring, follow these steps to encourage recovery:

1. Fluff Up the Grass: Gently rake or use a leaf blower to lift matted grass and improve air circulation. Avoid power raking, as this can rip out fragile grass.

2. Increase Sunlight and Airflow: Snow mold thrives in moist, shaded areas, so allowing sunlight to reach the affected spots will help dry them out.

3. Overseed Thin Areas: If the damage is extensive, overseeding can help restore lawn density.

4. Fertilize Wisely: Use a balanced fertilizer once your lawn begins active growth, avoiding high nitrogen applications in late fall to prevent future outbreaks.

5. Aerate and Dethatch (Later in the Season): Once your lawn is actively growing, aeration and dethatching can improve soil health and reduce conditions favorable to snow mold.

How to Prevent Snow Mold Next Winter

Prevention is key to avoiding snow mold outbreaks. Follow these steps to minimize the risk:

• Mow Properly Before Winter: Keep your grass at an appropriate height (around 2-2.5 inches) to prevent excessive moisture retention.

• Avoid Late-Season High Nitrogen Fertilizers: Opt for a slow-release, balanced fertilizer in the fall instead of a nitrogen-heavy formula.

• Improve Lawn Drainage: Aerate compacted soil to reduce water retention before winter.

• Remove Excess Thatch: A thick thatch layer can trap moisture, so occasional dethatching can help.

• Clear Leaves and Debris: Keep your lawn free of organic material that could create a damp environment under the snow.

• Manage Snow Accumulation: Avoid large piles of snow in one spot, as they take longer to melt and increase the risk of snow mold.

Get Professional Help with Spring Lawn Recovery

Snow mold can be frustrating, but a proper spring cleanup can help your lawn recover quickly. Our Spring Cleanup Service at Yardona helps break up snow mold using powerful backpack blowers to fluff up matted grass and improve airflow. Book your spring cleanup today and give your lawn the best start to the growing season!

Learn More About Our Spring Cleanup Services