FREE CANADIAN TOOL · CALCULATED FROM YOUR FIRST FROST
Fall Garden Countdown
Pick your city and get every job left before freeze-up, dated — worked out from your own average first fall frost.
What is left to do in the garden this fall?
Almost every autumn job is defined relative to first frost: overseed the lawn about six weeks before it, plant garlic about two weeks after it, apply winterizer once growth stops but before the ground freezes, and mulch perennials only after the ground has frozen. Because first frost runs from late August on the northern Prairies to late November on the coast, those dates only mean anything per city. Pick yours and the tool works out each deadline from Environment and Climate Change Canada climate normals.
Pick your city above to see your fall schedule.
How these dates are worked out
Every job is pinned to your average first fall frost, taken from Environment and Climate Change Canada climate normals. The offsets are ordinary Canadian practice: overseed about six weeks before frost so grass roots before freeze-up, plant garlic about two weeks after it so cloves root without sprouting, apply winterizer once the lawn stops growing but before the ground freezes, and mulch perennials only after the ground has frozen — mulching early houses voles and delays dormancy. Last-sowing dates add two weeks to a crop's days-to-maturity, because growth slows as light drops.
Frequently Asked Questions
When should I plant garlic in Canada?
Two to four weeks after your average first fall frost — cold enough that the cloves won't sprout before winter, early enough that they root before the ground freezes. Because first frost runs from late August on the northern Prairies to late November on the coast, the actual date varies by two months across the country. Pick your city above for yours.
When should I mulch perennials?
Only after the ground has frozen, roughly six weeks past first frost. Mulching early is the most common mistake: it gives voles shelter and delays dormancy. Winter mulch isn't there to keep roots warm — it's there to stop freeze-thaw cycles heaving plants out of the soil.
When do I apply winterizer fertilizer?
About three weeks after first frost — the lawn has stopped growing but the ground hasn't frozen. Use a low-nitrogen, high-potassium formula. It's the most valuable single application of the Canadian lawn year and the one most people skip.
Is it too late to sow anything?
It depends how many days are left before your frost. This tool gives the last-sowing deadlines; for a crop-by-crop answer use Can I Still Plant This. Under a cold frame or row cover, add roughly two weeks to any deadline.
Where do these dates come from?
Your city's average first fall frost, from Environment and Climate Change Canada climate normals. Every task is calculated from that date rather than stored, so nothing goes stale — if a city's frost date is corrected, the whole schedule follows.