Yes, the final cut is one of the most important steps in preparing your turf for the cold season. This strategic action directly influences the health and resilience of your grass during its dormant period. Proper preparation helps prevent common winter issues and ensures a healthier, faster green-up when spring returns. The timing and height of this final cut must be executed correctly to maximize the benefits for your lawn.
Why the Final Cut is Essential for Winter Health
Leaving grass blades too long before winter encourages the development of fungal diseases, particularly snow mold. When long grass, typically over three inches, is pressed down by snow or heavy moisture, it mats together, trapping humidity. This creates a cool, damp space ideal for fungal growth beneath the snowpack. This matted turf can suffocate the grass crowns and lead to large, dead patches visible when the snow melts in spring.
Shorter grass also deters pests that can damage the lawn over winter. Rodents like voles prefer to nest and travel undetected beneath the cover of tall grass, where they feed on the grass crowns and roots. Removing this protective layer makes the area less hospitable for these burrowing animals, reducing the likelihood of extensive root damage.
A shorter blade allows the grass plant to focus its energy reserves efficiently. Grass prepares for winter by storing carbohydrates in its root system, a process known as hardening. If the blades are too long, the plant expends energy maintaining the excess leaf tissue instead of maximizing the storage of food reserves in the roots, which are needed to survive the winter and fuel the initial growth spurt in spring.
The Optimal Timing and Cutting Height
The final cut should be timed by the cessation of active grass growth, not a specific calendar date. This typically occurs when daytime temperatures consistently drop below 50°F, signaling the grass is entering its natural dormancy period. The noticeable slowdown in growth ensures the grass will not grow tall enough to mat down before the snow arrives.
The ideal height for most cool-season grasses is between 2 and 2.5 inches. This height is short enough to prevent the matting that leads to snow mold, yet long enough to protect the grass crowns and root system from extreme cold. Cutting the grass shorter than two inches risks scalping the lawn, which can damage the roots and interrupt the photosynthesis process needed for final carbohydrate storage.
To achieve this lower height without stressing the plant, use a gradual reduction technique over the last few weeks of the season. Instead of dropping the mower blade drastically for the final cut, lower the deck setting by half an inch for each of the last two or three mowing sessions. This conditioning allows the grass to adjust to the shorter length, minimizing shock before the mower is put away for the season.
Post-Mow Winterization Checklist
Once the final cut is complete, several follow-up steps are necessary to prepare the lawn for winter dormancy.
Applying a specialized “winterizer” fertilizer is recommended, as this is the last opportunity to feed the root system before the ground freezes. These late-fall formulas are high in nitrogen and potassium, which help the grass store nutrients in the roots and strengthen cell walls for improved cold and disease tolerance.
Complete removal of all fallen leaves and debris is essential after the final mow. A thick layer of leaves traps moisture and blocks sunlight, creating damp, low-oxygen conditions that promote snow mold and can suffocate the turf. Raking or mulching the leaves ensures the grass blades remain exposed to air, preventing fungal issues.
Finally, prepare the equipment for storage. For gasoline-powered mowers, either run the engine until the fuel tank is completely empty or add a fuel stabilizer. This prevents the gasoline from oxidizing and causing clogs or corrosion over the winter. Cleaning the mower deck and sharpening the blade now ensures the equipment is ready for the first cut of the following spring.