The Home Almanac

Vol. I, MMXXVIThe Canadian home, in season655 stations, every province and territory

Lawn Calendar

First mow, overseed window, last feed, last cut, and snow-mold watch. Computed for your exact place from the 30-year climate record at your nearest station.


First mow Set your place
Overseed
Last fertilizer
Last mow

Lawn dates for your place, with reminders.

Weekend work window: Check the live forecast and task windows for your place on the Weather page before you head outside.

American Homestead Summer, a Currier and Ives lithograph of a farmhouse in full summer
American Homestead Summer. Currier and Ives, New York, 1868.

Lawn dates for major cities

Computed from each city's own station normals. Your town's dates may differ; use the planner above for your exact place.

CityFirst mowOverseedLast mow
Vancouver, BC April 20 September 15 - October 13 October 27
Victoria, BC April 25 September 10 - October 8 October 22
Kelowna, BC April 26 August 3 - August 31 September 14
Calgary, AB May 17 July 22 - August 19 September 2
Edmonton, AB May 14 July 18 - August 15 August 29
Saskatoon, SK May 9 July 21 - August 18 September 1
Regina, SK May 9 July 18 - August 15 August 29
Winnipeg, MB May 8 July 28 - August 25 September 8
Thunder Bay, ON May 19 July 3 - July 31 August 14
Sudbury, ON May 10 August 6 - September 3 September 17
Ottawa, ON May 1 August 12 - September 9 September 23
Toronto, ON April 30 August 21 - September 18 October 2
Windsor, ON April 20 September 4 - October 2 October 16
Montreal, QC April 30 August 17 - September 14 September 28
Quebec City, QC May 10 August 9 - September 6 September 20
Fredericton, NB May 10 July 31 - August 28 September 11
Halifax, NS May 15 August 23 - September 20 October 4
Charlottetown, PE May 20 August 22 - September 19 October 3
St. John's, NL June 9 August 22 - September 19 October 3
Whitehorse, YT June 1 June 30 - July 28 August 11
Yellowknife, NT June 3 July 24 - August 21 September 4
Iqaluit, NU July 2 July 15 - August 12 August 26

Method: monthly mean temperature normals anchored mid-month, linear interpolation across 10 C (first mow) and 7 C (growth slowdown). Frost offsets use the station's average first fall frost. Read the full methodology.

Field notes

The dates above are the 30-year average. This is the lawn season people nearby are actually having. Add what you are seeing, read what your neighbours saw.

Set your place above to read and add notes for your town.

Questions, answered plainly

When should I mow my lawn for the first time in spring?

Wait until the soil has warmed enough that grass is actively growing, roughly when the monthly mean temperature crosses 10 C. In Toronto that is mid to late April; in Ottawa or Montreal, late April to early May; in Calgary or Edmonton, early to mid May. Mowing too early on cold, wet soil compacts the root zone.

When should I overseed my lawn in Canada?

Late summer, four to eight weeks before the average first frost. The soil is still warm for fast germination, but nights are cool enough that the new grass hardens off before winter. In Toronto that means mid August to mid September; in Halifax, mid August to early September; in Winnipeg, mid August.

When is the last fertilizer application?

About six weeks before the first frost. Any later and the nitrogen pushes soft, sappy growth that is vulnerable to winter injury. The tool above computes the date from your station normals.

Why is the last mow important for snow mold?

Long grass matting under heavy, wet snow is the main snow-mold habitat. The final cut should be slightly shorter than summer height, but never scalped, and timed before the ground freezes and snow settles.