When to Plant Green Beans in Ottawa, ON
Published: April 24, 2026 · Updated: April 27, 2026
One of the easiest and most productive direct-sow vegetables. Bush beans need no support and produce in 50–60 days; pole beans need a trellis but produce for months.
Ottawa's Canadian Zone 5b (USDA 5a) continental climate brings cold winters, hot summers, and higher frost risk than Toronto thanks to the inland location. The 153 frost-free days from early May through early October is adequate for most vegetables, but variety selection — short-season cultivars under 70 days — matters significantly.
Green Beans Planting Calendar for Ottawa
Direct sow outdoors: May 13–23
Harvest window: July 2 – July 17
Minimum soil temperature: 16°C (60°F)
Days to harvest: 50–65 days
Sun requirement: Full sun
Fall crop planting: August 11–21 (harvest September 30)
Ottawa Climate Notes
Ottawa Valley winters are harsh. Choose short-season tomato varieties under 70 days (Stupice, Sunrise, Sub-Arctic Plenty) and transplant only after the May long weekend. Fall garden extends the productive season into October with cold-tolerant greens and brassicas.
Growing Tips for Green Beans
- Direct sow only — beans do not transplant successfully.
- Succession plant every 2–3 weeks for continuous harvest throughout the season.
- Do not over-fertilize with nitrogen — beans fix their own nitrogen from the soil.
- Harvest every 2 days at finger-length; leaving beans on the vine signals the plant to stop producing.
Companion Planting in Ottawa
Pair green bean with Carrot, Cucumber, Summer Savory, Marigold for mutual benefit. Avoid planting near Onion, Garlic, Fennel, which compete with or inhibit green bean growth.
Pests and Problems to Watch in Ottawa
The most common pest and disease pressure on green beans in Ottawa comes from Mexican Bean Beetle, Aphids, Spider Mite, Bean Mosaic Virus. Floating row covers through the first 4–6 weeks after planting block adult pests from laying eggs, and a weekly scouting routine catches infestations before they damage the crop.
Other Ontario Cities
Frequently Asked Questions
When do I plant green bean in Ottawa?
Ottawa's last spring frost is around May 6. Direct sow May 13–23.
What Canadian hardiness zone is Ottawa?
Ottawa is in Canadian Zone 5b (USDA equivalent 5a). The continental inland climate delivers 153 frost-free days from May 6 to October 6, which shapes every planting date in the local calendar.
How long is Ottawa's growing season?
Ottawa has 153 frost-free days — from May 6 in spring to October 6 in fall. That is more than enough time to finish a full green bean crop (50–65 days to maturity) before the first fall frost.
Can I grow green bean in containers in Ottawa?
Yes. Container growing on balconies and decks is practical in Ottawa — choose a 5-gallon or larger dark-coloured container to warm the root zone, use a high-quality potting mix, and water daily during hot summer weather. In milder climates, containers extend both spring and fall windows by several weeks.
What is the first fall frost in Ottawa?
Ottawa's average first fall frost is October 6. For a fall green bean crop, plant around August 11–21 so plants mature before the first killing frost.