I see lots of folks who stop mowing their lawns in October. But to properly prepare your lawn for winter, the final cut for NH and VT lawns should be from early to late November. The final November mowing should be short, 1.5 to 1.75”.
Why mow short as the last cut? Grass can keep growing under snow and long grass can become more susceptible to disease, thinning (especially with leaves on top) and winter damage. And in the spring, a shorter length helps warm the soil faster – leading to an earlier green-up.
Don’t forget about leaves and fall debris. Leaf piles or heavy leaf cover, especially in shaded areas, can actually mulch and or thin turf. Better to do nothing with leaves then create large piles like they Egyptian pyramids only to leave them until spring. With the leaves gone and increased sunlight in shaded areas, keep your lawn raked to allow for extra healthy late fall growth in November or even early December.
Don’t undue any gains made this fall by allowing your lawn to enter winter too long or buried in leaves. Voles will enjoy the protective cover and if present eat tunnels into the lawn surface. With last winter’s mild temperatures, I saw more vole damage than I have ever seen in my career.
So don’t retire your lawn mower, rake or leaf blower too early. Make one last short cut to 1.5 to 1.75” and get rid of those leaves – your lawn will thank you.