What to Plant in May in Ontario
Your May planting guide for Ontario (USDA Zones 3–7, typically Zone 5). We've broken out activities by zone — jump to yours below.
Growing season varies across Zones 3–7 — 120–210 days. Pick the zone that matches your part of the state.
🏠
711
Start Indoors
🌿
1363
Transplant Outdoors
🌱
1213
Direct Sow
🧺
305
Harvest
Ontario · Zones 3–7
Zone 5 May guideZone 5 — May in Ontario★ Most of ON
1814 varieties active · Last frost April 30 · 155-day season
Alfalfa Microgreens
Microgreens · 6-10d
Amara
Lettuce & Salad Greens · 21d
Amaranth Microgreens
Microgreens · 50d
Amaranth, Glitter Mix
Microgreens · 16-25d
Arugula
Lettuce & Salad Greens · 10-15d
Arugula 'Rocket'
Brassicas · 20-40d
Arugula Microgreens
Microgreens · 10-15d
Asian Delight
Lettuce & Salad Greens · 37d
Zone 4 — May in Ontario
552 varieties active · Last frost May 10 · 135-day season
Alfalfa Microgreens
Microgreens · 6-10d
Amara
Lettuce & Salad Greens · 21d
Amaranth Microgreens
Microgreens · 50d
Amaranth, Glitter Mix
Microgreens · 16-25d
Arugula
Lettuce & Salad Greens · 10-15d
Arugula 'Rocket'
Brassicas · 20-40d
Arugula Microgreens
Microgreens · 10-15d
Basil Microgreens
Microgreens · 74d
Zone 6 — May in Ontario
1831 varieties active · Last frost April 15 · 180-day season
Alfalfa Microgreens
Microgreens · 6-10d
Alpine
Root Vegetables · 55d
Amara
Lettuce & Salad Greens · 21d
Amaranth Microgreens
Microgreens · 50d
Amaranth, Glitter Mix
Microgreens · 16-25d
Arugula
Lettuce & Salad Greens · 10-15d
Arugula 'Rocket'
Brassicas · 20-40d
Arugula Microgreens
Microgreens · 10-15d
Zone 3 — May in Ontario
1110 varieties active · Last frost May 15 · 120-day season
Alfalfa Microgreens
Microgreens · 6-10d
Amara
Lettuce & Salad Greens · 21d
Amaranth Microgreens
Microgreens · 50d
Amaranth, Glitter Mix
Microgreens · 16-25d
Arugula
Lettuce & Salad Greens · 10-15d
Arugula Microgreens
Microgreens · 10-15d
Basil Microgreens
Microgreens · 74d
Basil, Lemon
Microgreens · 16-25d
Zone 7 — May in Ontario
1837 varieties active · Last frost April 1 · 210-day season
Alfalfa Microgreens
Microgreens · 6-10d
All Seasons White Daikon
Root Vegetables · 60-70d
Alpine
Root Vegetables · 55d
Amara
Lettuce & Salad Greens · 21d
Amaranth Microgreens
Microgreens · 50d
Amaranth, Glitter Mix
Microgreens · 16-25d
Amazing
Brassicas · 68d
Arugula
Lettuce & Salad Greens · 10-15d