Stop mowing when soil temps drop below 10°C — typically late October in the GTA. Final cut at 2–2.5 inches prevents snow mould. Month-by-month guide for Toronto, North York & Vaughan.
Stop mowing when soil temperature consistently drops below 10°C and grass growth has nearly stopped — typically late October in the GTA. Your final cut should leave the grass at 2–2.5 inches. This guide covers the month-by-month breakdown for Toronto, North York, Vaughan, Markham, Richmond Hill, and Scarborough.
Stop mowing when soil temp drops below 10°C — typically late October in the GTA. Your final cut should leave the grass at 2–2.5 inches (shorter than your summer height). Do not skip the final mow — long grass over winter causes snow mould and vole damage. Do not scalp the lawn — going below 2 inches causes frost damage to grass crowns.
Grass is still actively growing in September. Continue your regular mowing schedule. Soil temperatures are above 15°C across the GTA and growth rate remains strong. Maintain your summer height of 3–3.5 inches.
Early October still sees good grass growth in the GTA. Soil temperatures drop toward 12–14°C. Some slowing of growth begins, but the lawn still needs regular cuts. Start thinking about scheduling your fall cleanup and finalizing your last mow date.
Soil temperatures drop toward 10–12°C by mid-October. Growth slows noticeably — your lawn may only need cutting every 10–14 days. Begin gradually lowering your cut height toward 2.5 inches.
Late October is the ideal time for your last mow of the season in most of the GTA. Soil temperatures are at or near 10°C, grass growth has nearly stopped. Cut to 2–2.5 inches — your winter height.
Once soil temperatures drop below 10°C consistently, stop mowing. The grass is dormant. Mowing dormant grass tears the crowns, stresses the plant, and can cause winter injury.
When grass is growing less than half an inch per week, it no longer needs weekly cutting. This typically happens in mid to late October in the GTA.
Grass almost completely stops growing below 10°C soil temperature. In the GTA, this threshold is typically crossed in the last week of October.
If you mow and the grass is nearly the same height 7 days later, growth has effectively stopped. This is the clearest practical sign that the season is over.
Once the GTA has had its first hard frost, grass is dormant. Don't mow after a hard frost — the frozen cells shatter when cut.
In most of Ontario, including the GTA, you should stop mowing when the soil temperature consistently drops below 10°C and grass growth has nearly stopped. This typically happens in the last week of October in Toronto, North York, Vaughan, Markham, Richmond Hill, and Scarborough. Your final mow should leave the grass at 2–2.5 inches.
Grass that goes into winter too long (above 3.5 inches) flops over and mats down, creating conditions for snow mould — a fungal disease that leaves circular dead patches when the snow melts. Long grass also provides habitat for voles that tunnel under the snow and feed on grass roots.
Yes — but not too short. The ideal winter height is 2–2.5 inches. This is shorter than your summer growing height (3–3.5 inches) to prevent matting and snow mould, but not so short that you expose grass crowns to frost damage. Never scalp the lawn below 2 inches before winter.