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Can You Grow Watermelon in Ontario?

Canada · Canadian Zone 5 · zones 3, 4, 5, 6, 7

Grows well here

Watermelons thrive here — they love the long warm season your zone provides.

Plant zones

4b–11b

Ontario last frost

mid-April

Ontario first frost

mid-October

Days to harvest

70–90 days

When to plant Watermelons in Ontario

Start indoors

Mar 18

Transplant

Apr 15

Harvest

Jun 24 – Jul 14

Dates are approximate, based on Ontario's average frost dates. Your exact yard may vary by microclimate.

About Watermelon

Watermelons love heat space and sun — they are a rewarding crop but need a long warm season.

Start indoors 4 weeks before last frost. Transplant carefully — watermelons hate root disturbance. Give them maximum space. Use black plastic mulch to warm soil. Choose icebox varieties for containers.

Full watermelon growing guide →

Gardening in Ontario

Ontario spans several climate zones. Northern Ontario is Zone 3-4 with short seasons; southern Ontario is Zone 5-7 with long productive seasons. The Niagara Peninsula is one of Canada's premier fruit-growing regions.