What is the most important time for lawn care in Canada?

Late August through September. Warm soil and cooler nights make it the best window to overseed, dethatch and feed.

When should I fertilize my lawn in Canada?

Once in late spring when the grass is growing, again in early fall, and a late fall feeding before the ground freezes.

Can I use weed killer on my lawn?

It depends on the province. Ontario and several others ban cosmetic pesticides on lawns and allow only lower-risk products, such as some iron-based weed killers.

When should I rake after winter?

Once the snow is gone and the lawn has dried enough not to squelch. Raking soggy grass pulls out crowns.

Lawn Care Calendar for Canada: What to Do Month by Month

Lawn care follows the grass, not the calendar. Kentucky bluegrass, fescues and ryegrass grow most in spring and fall and slow down in summer heat. This schedule fits southern Ontario and southern Quebec; the Prairies and the north run a few weeks later, coastal BC a few weeks earlier.

What should you do each month?

Month	Main jobs
January	Keep off snow-covered lawn paths. Service the mower.
February	Sharpen the blade. Avoid piling salty snow on the lawn.
March	Stay off soggy grass as the snow melts.
April	Rake out matted patches and snow mold once the lawn dries.
May	First mows. First feeding once growth is steady. Seed bare spots.
June	Mow at about 6 to 7 cm. Water deeply or let the lawn go dormant.
July	Mow high, skip fertilizer in heat, check for grubs.
August	Late August: start fall renovation, core aerate.
September	Overseed, dethatch, feed and treat weeds where allowed.
October	Keep mowing, mulch leaves, second fall feeding.
November	Last mow, final feeding before freeze-up, drain irrigation.
December	Rest.

What does the app’s calendar show?

What a Green Lawn builds a week-by-week task list from the lawn’s location, grass type and mowing height. For a lawn in Toronto, the week of September 7 looks like this:

Calendar tasks in the What a Green Lawn app for a lawn in Toronto — Toronto, September 20, 2026: the week of September 7 with weed control, scarify and overseed (fall).

Across the year the calendar puts feeding in April, May and September to November, weed control at the start of each month from March to October, dethatching in April and September, overseeding in May and September, a spring cleanup in March, leaf clearing in October and a soil pH check in September. December to February are rest months. Its dates follow a single northern schedule, so in Canada treat the March and April tasks as “once the snow is gone”.

Which weed control is allowed?

Pest control products in Canada carry a registration number under the Pest Control Products Act. On top of that, Ontario and several other provinces ban cosmetic pesticide use on lawns and allow only lower-risk active ingredients, including some iron-based weed killers. Check your province’s rules before you buy, and remember that a thick lawn mowed high keeps out most weeds.

How do you adjust the calendar to your region?

Watch the grass and the soil, not the date. Soil temperature is the best guide for seeding, see soil temperature for lawns. See also first and last mow of the year and when to fertilize your lawn. Lime only on acidic soil, see lawn lime and soil pH.

What a Green Lawn turns this calendar into weekly tasks for your own lawn, with the forecast and soil estimate on the same screen.