When to Stop Mowing in the Fall

November 21, 2017

When to stop mowing in the fall is a perennial question. Some homeowners stop as soon as the frost hits, but as warm weather is pushing frost dates from early- to mid-October into late October and early November, this is a bad idea.  Leaving your lawn too long over the winter can leave it vulnerable to disease and will make your first mow in the spring more challenging.

Rather than focusing on a date when you think you it is okay to stop mowing, make the decision to stop based on what your grass is doing. This will depend on both your zone, the current weather patterns, your microclimate (urban heat islands versus rural areas), and whether you have a cool season or a warm season grass. Cool season grasses like fescue, rye grass and Kentucky blue grass will grow at a faster rate through the cooler fall days than warm season grasses like bermuda or zoysia grass.

While your grass is growing, you should keep cutting it. If growth has slowed, you may be able to stretch the period between mowing, or you can adjust the mower height and take a little less off. Once the grass has stopped growing, give it a final, shorter trim—about two inches for cool season grasses—to keep it tidy through the winter and to protect it from diseases like snow mold, which can occur if it snows before the grass is completely dormant. Be sure your mower blades are sharp before that final trim, as torn or damaged grass leaves can lead to disease.

In the event of a freak snow or ice storm followed by a return to warmer, dryer temperatures for an extended period of time, use caution. Be sure that the grass has dried thoroughly before you try to mow, and do not do so immediately after, while the grass is frozen or wet.

If necessary after your final mow, you should continue to rake or mulch your leaves; if you rake, you may wish to use a quick-release fertilizer on your lawn. The roots will absorb the nitrogen over the winter, giving your lawn a boost in the spring. Use a quick release rather than a slow release formula, because you don’t want too much nitrogen in the spring when grass will have its main growth period anyway. Aerating the lawn will allow the fertilizer and oxygen to penetrate deeper into the soil. Aerating will also break up the thatch layer, which will result in better growth in the spring.

While you may be tired of mowing by late-October or early-November, keep it up so long as your grass grows. Doing so will help protect your lawn from disease over the winter, and set you up for a healthier, lusher lawn in the spring.