When to Plant Eggplant in Ontario
Published: April 24, 2026 · Updated: April 27, 2026
Warm-season nightshade requiring the longest indoor start of any common vegetable — 8–10 weeks before last frost. Needs soil above 15°C and consistent summer heat; intolerant of cold below 10°C.
Eggplant grow well in this province with appropriate variety selection and standard Canadian planting timing.
Eggplant Planting Window for Ontario
Start seeds indoors: February 16–23 (varies by city — earliest in southern Ontario, latest on the Prairies)
Transplant outdoors: May 11–21 (after last frost in your city)
Minimum soil temperature: 16°C (60°F)
Days to harvest: 65–80 days
Sun requirement: Full sun (8+ hours)
⚠ Start eggplant indoors 8–10 weeks before last frost — same timing as peppers. Transplant 2–3 weeks after last frost when soil is above 60°F. Needs heat and full sun. Does not tolerate cold — protect from temps below 50°F.
Ontario Cities — Eggplant Planting Dates
City-specific frost dates and eggplant planting windows for Ontario.
Growing Eggplant in Ontario
- Use a heat mat during germination — eggplant seeds need 24–27°C soil to sprout reliably.
- Protect transplants from cold spring nights — temperatures below 10°C halt growth for weeks.
- Use stakes or small cages — eggplant stems bend or break under the weight of mature fruit.
- Harvest while fruit skin is glossy; dull skin signals an over-ripe, bitter, seedy interior.
Companion Planting for Eggplant
In Ontario gardens, pair eggplant with Pepper, Bean, Basil, Marigold. Avoid planting near Fennel, Brassicas, which compete with or inhibit eggplant growth.
Common Pests and Problems
Eggplant in Ontario are commonly affected by Flea Beetle, Colorado Potato Beetle, Spider Mite, Verticillium Wilt. Floating row covers installed at planting block most adult pests from laying eggs, and a weekly scouting routine catches infestations before they damage the crop.
Frequently Asked Questions
When should I plant eggplant in Ontario?
In Ontario (Canadian Zones 5b–6b), start seeds indoors around February 16 and transplant around May 11. Eggplant grow well in this province with appropriate variety selection and standard Canadian planting timing.
What is the best eggplant variety for Ontario?
Ontario gardeners should prioritise varieties bred for shorter seasons or Canadian climates. For eggplant in Canadian Zones 5b–6b, look for cultivars labelled under 80 days to maturity. Local nurseries and provincial seed exchanges curate varieties that ripen within Canadian frost-free windows.
How does Ontario's climate affect eggplant?
Ontario spans Canadian Zones 5b–6b with frost-free seasons ranging from roughly 153 to 195 days. Eggplant need warm soil (16°C minimum) and steady heat, so timing transplants correctly is critical — too early and plants sit in cold soil; too late and frost cuts the season short.
Can I grow eggplant in containers in Ontario?
Yes. Container growing on balconies and patios extends the viable growing area across every Canadian province. Dark-coloured containers warm up faster in spring and extend the season on both ends. Choose a 5-gallon or larger pot for eggplant and water daily during hot summer weather, since containers dry out quickly.
When is the first fall frost in Ontario?
First fall frost dates in Ontario range from October 15 in the coldest areas to November 1 in the warmest. Most eggplant plantings in Ontario are spring-timed to harvest before the first fall frost rather than as a second fall crop.