Growing Leek in Zone 4b
Zone 4b has cold winters and a moderate growing season. Timing is key for Leek in this zone. Last frost: May 1. First frost: Oct 5.
Planting Calendar
Season: May 1 – Oct 5 (157 days)
When to Plant Leek in Zone 4b
Start Seeds Indoors: Feb 20
Start Leek seeds indoors around Feb 20 (10 weeks before last frost). Optimal germination temperature: 70°F. Germinates in 7–14 days.
Transplant Outdoors: Apr 17
Transplant Leek seedlings outdoors after Apr 17. Wait until soil temperature reaches 45°F. Space plants at 4/sqft (6" apart). Harden off plants for a week before moving outside.
Harvest: Jul 16
First harvest approximately Jul 16 (~90 days from transplant). Continue harvesting until first frost (Oct 5). Leek can overwinter in mild climates for continued harvest.
Companion Planting
Leek in Other Zones
1a 1b 2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a 8b 9a 9b 10a 10b 11a 11b 12a 12b 13a 13bPlan Your Leek Garden
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