When to Plant Onions in Regina, SK
Published: April 24, 2026 · Updated: April 27, 2026
Onion timing is determined by day-length as much as frost dates. Use short-day varieties south of 35°N latitude (TX, FL, CA) and long-day varieties north of 35°N (OH, MN, NY).
Regina's Canadian Zone 3b (USDA 3a) semi-arid continental climate is very similar to Saskatoon but Regina is one of Canada's windiest cities — wind protection is critical for young plants. At 125 frost-free days and minimal natural windbreaks on the flat prairie, sheltered microclimates matter.
Onions Planting Calendar for Regina
Start seeds indoors: March 9–16
Transplant outdoors: April 20–30
Direct sow outdoors: April 20–30
Harvest window: July 19 – August 18
Minimum soil temperature: 2°C (35°F)
Days to harvest: 90–120 days
Sun requirement: Full sun
⚠ CRITICAL: Choose variety based on your latitude. Short-day varieties for south of 35°N (Texas, Florida, California). Long-day varieties for north of 35°N (Ohio, Minnesota, New York). Intermediate varieties work in the middle band.
Regina Climate Notes
Regina's flat terrain offers no natural windbreaks. Use a sheltered south-facing garden wall or fence to create a warmer microclimate. Black plastic mulch warms soil 2-4°C and extends the effective season. Wind-resistant varieties and windbreak planting are standard practice for serious Regina gardeners.
Growing Tips for Onions
- Match variety to latitude: short-day south of 35°N, long-day north of 35°N, intermediate in between.
- Growing from sets (small bulbs) is fastest; growing from transplants gives the most variety options.
- Reduce watering as tops begin to fall over — dry conditions encourage tight, firm bulbs that store longer.
- Cure harvested onions 2–4 weeks in a warm, dry, airy location before storing — uncured onions rot quickly.
Companion Planting in Regina
Pair onion with Carrot, Tomato, Lettuce, Beet for mutual benefit. Avoid planting near Bean, Pea, Asparagus, which compete with or inhibit onion growth.
Pests and Problems to Watch in Regina
The most common pest and disease pressure on onions in Regina comes from Onion Thrips, Onion Maggot, Downy Mildew, Neck Rot. 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 Saskatchewan Cities
Frequently Asked Questions
When do I plant onion in Regina?
Regina's last spring frost is around May 18. Start seeds indoors March 9–16. Transplant outdoors April 20–30.
What Canadian hardiness zone is Regina?
Regina is in Canadian Zone 3b (USDA equivalent 3a). The semi-arid windy Prairie climate delivers 125 frost-free days from May 18 to September 20, which shapes every planting date in the local calendar.
How long is Regina's growing season?
Regina has 125 frost-free days — from May 18 in spring to September 20 in fall. That is more than enough time to finish a full onion crop (90–120 days to maturity) before the first fall frost.
Can I grow onion in containers in Regina?
Yes. Container growing on balconies and decks is practical in Regina — 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 Canadian Zone 3–4, a sheltered south-facing location adds 2–3 weeks to the effective season.
What is the first fall frost in Regina?
Regina's average first fall frost is September 20. Most onion in Regina is a single spring-timed planting designed to harvest before the first fall frost.