Gardening in Ontario
Ontario ranges from Zone 3 north of Sudbury to Zone 7 in the Niagara Peninsula. The Great Lakes moderate temperatures, extending growing seasons and enabling wine grapes, tree fruits, and incredible vegetable diversity.
Today's Tip for Ottawa
March 2026 Planting Guide
Zone 5J
F
M
A
M
J
J
A
S
O
N
D
Growing
Shoulder
This month
| Task | March – Zone 5 |
|---|---|
| Start Indoors | Tomatoes, peppers (6-8 wks pre-frost) |
| Direct Sow | Spinach, radish in cold frame (Zone 6+) |
| Key Tasks | Prune dormant fruit trees |
Frost Dates – Ottawa
🌸
Last Spring Frost
Late April
🍂
First Fall Frost
Mid October
Frost-free period: ~155 days. Always verify with Environment Canada forecasts — dates can vary ±2 weeks based on elevation and microclimate.
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