When to Plant Annuals in Toronto, ON – 2026
Published: April 27, 2026
Toronto is in Canadian Zone 6b (Great Lakes temperate). Last spring frost averages April 20; first fall frost November 1; the growing season runs about 195 frost-free days. Plant annuals in Toronto from cool-season 2-4 weeks before victoria day. warm-season after may 18 (victoria day)..
Annuals Planting Window for Toronto, ON
Plant warm-season annuals (petunias, zinnias, impatiens, begonias) after last frost when soil reaches 15°C / 60°F. Cool-season annuals (pansies, snapdragons, alyssum) can be planted 2–4 weeks before last frost. Start from seed indoors 6–8 weeks before transplanting.
For Toronto, ON specifically, the recommended planting window is Cool-season 2-4 weeks before Victoria Day. Warm-season after May 18 (Victoria Day).. Lake Ontario extends the growing season 2-3 weeks compared to inland Ontario. Toronto gardeners enjoy one of Canada's longest productive windows. Heirloom and heat-loving varieties that struggle farther north (eggplant, melons, sweet potato) succeed reliably here.
Annuals complete their lifecycle in one Canadian growing season. Cool-season annuals (pansies, snapdragons, alyssum) tolerate frost down to -7°C. Warm-season annuals (petunias, zinnias, marigolds, impatiens) are killed by any frost.
Best Annuals Varieties for Toronto, ON
For Toronto, ON (Canadian Zone 6b), choose varieties rated for your zone or one zone colder for reliable winter survival. The Canadian-bred or tested varieties below perform well in Ontario conditions.
Self-cleaning, no deadheading needed. Continuous bloom from late spring through first fall frost. Ideal for Canadian summer hanging baskets.
Powdery mildew resistant. Direct sowing works on the Prairies once soil reaches 12°C. Heat-tolerant — excellent for Calgary and Saskatoon summers.
Most reliable Canadian annual. Tolerates the wide diurnal temperature range typical of Calgary and Edmonton summers.
Cool-season annual that tolerates light frost — can go out 2 weeks before Victoria Day. Often blooms into November in mild Canadian falls.
Cool-season annual that bloom strongly in cool Canadian springs and falls. Often winter over in Zone 7-8 BC. Annual elsewhere.
How to Plant Annuals in Toronto
Sow method: transplant or direct. The steps below adapt the general planting advice for Toronto, ON's climate and timing.
- →Warm-season annuals: plant after last frost when soil reaches 15°C (60°F).
- →Cool-season annuals: plant 2 to 4 weeks before last frost or in fall (Zone 7+) for spring or winter color.
- →For earliest blooms, start seeds indoors 6 to 8 weeks before last frost; transplant after frost.
- →Choose full sun for most annuals (zinnias, marigolds, petunias) and part shade for shade-loving types (impatiens, begonias).
- →Space according to mature size — typically 25 to 30 cm (10 to 12 inches) for most bedding annuals.
- →Water at the base; avoid overhead watering which promotes powdery mildew on zinnias.
Frequently Asked Questions about Annuals in Toronto, ON
When can I plant annuals in Toronto?
Plant annuals in Toronto from cool-season 2-4 weeks before victoria day. warm-season after may 18 (victoria day). based on the city's Canadian Zone 6b. Last spring frost: April 20; first fall frost: November 1; frost-free growing season: 195 days.
What Canadian zone is Toronto?
Toronto is in Canadian Zone 6b (USDA equivalent 6a). The climate is great lakes temperate. Lake Ontario extends the growing season 2-3 weeks compared to inland Ontario. Toronto gardeners enjoy one of Canada's longest productive windows. Heirloom and heat-loving varieties that struggle farther north (eggplant, melons, sweet potato) succeed reliably here.
Are annuals winter-hardy in Toronto?
Annuals complete their lifecycle in one Canadian growing season. Cool-season annuals (pansies, snapdragons, alyssum) tolerate frost down to -7°C. Warm-season annuals (petunias, zinnias, marigolds, impatiens) are killed by any frost.