Green Onion illustration

Growing Green Onion in Zone 4b

Zone 4b has cold winters and a moderate growing season. Timing is key for Green Onion in this zone. Last frost: May 1. First frost: Oct 5.

Planting Calendar

Indoor
Outdoor
Harvest
Mar 20Oct 5

Season: May 1 – Oct 5 (157 days) · Succession: plant every 3 weeks (up to 4x)

Zone4b
Last FrostMay 1
First FrostOct 5
Season Length157 days
Days to Harvest65
Sunfull-to-part
Frost ToleranceHeavy
Spacing16/sqft (3" apart)

When to Plant Green Onion in Zone 4b

Start Seeds Indoors: Mar 20

Start Green Onion seeds indoors around Mar 20 (6 weeks before last frost). Optimal germination temperature: 65°F. Germinates in 7–14 days.

Transplant Outdoors: Apr 17

Transplant Green Onion seedlings outdoors after Apr 17. Wait until soil temperature reaches 40°F. Space plants at 16/sqft (3" apart). Harden off plants for a week before moving outside.

Harvest: May 27

First harvest approximately May 27 (~40 days from transplant). Continue harvesting until first frost (Oct 5). Green Onion can overwinter in mild climates for continued harvest.

Fall Planting: Aug 10

For a fall harvest, plant Green Onion around Aug 10 (8 weeks before first frost).

Companion Planting

❌ Bean❌ Pea

Plan Your Green Onion Garden

Track Green Onion from seed to harvest with personalized frost dates, watering recommendations, and companion planting visualization.

Start Free Green Onion Growing Guide