
When to Plant Peas in Ottawa, ON
Published: April 24, 2026 · Updated: April 27, 2026

One of the first vegetables of spring — peas go in 4–6 weeks before last frost when soil is just workable. Tolerate light frost and actually prefer cool temperatures under 70°F.
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.
Peas Planting Calendar for Ottawa
Direct sow outdoors: April 1–11
Harvest window: May 26 – June 10
Minimum soil temperature: 4°C (40°F)
Days to harvest: 55–70 days
Sun requirement: Full sun to partial shade
Fall crop planting: July 28–August 7 (harvest September 21)
⚠ Plant peas 4–6 weeks before last frost — one of the first vegetables of spring. Tolerate light frost. Also plant in late summer for a fall harvest.
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 Peas
- Soak pea seeds overnight before planting to speed germination in cool soil.
- Install a 4–6 foot trellis at planting time — peas climb from day one and produce more per square foot when supported.
- Sow every 2 weeks through early spring for a continuous 6-week harvest window.
- Plant a second crop 10–12 weeks before first fall frost for autumn harvests; shade cloth helps germination in warm soil.
Companion Planting in Ottawa
Pair pea with Carrot, Radish, Cucumber, Corn for mutual benefit. Avoid planting near Onion, Garlic, Chive, which compete with or inhibit pea growth.
Pests and Problems to Watch in Ottawa
The most common pest and disease pressure on peas in Ottawa comes from Pea Aphid, Powdery Mildew, Root Rot, Pea Weevil. 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 pea in Ottawa?
Ottawa's last spring frost is around May 6. Direct sow April 1–11.
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 pea crop (55–70 days to maturity) before the first fall frost.
Can I grow pea 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 pea crop, plant around July 28–August 7 so plants mature before the first killing frost.