When should I plant Leek in Zone 4a?

Start Leek seeds indoors around Feb 24. Transplant outdoors after Apr 21. Expect first harvest around Jul 20.

What is the last frost date for Zone 4a?

The average last spring frost date for Zone 4a is May 5. The first fall frost averages Oct 1, giving a 149-day growing season.

Can I grow Leek in Zone 4a?

Yes. Leek needs 120 days to harvest. Zone 4a has a 149-day growing season, which is sufficient.

Growing Leek in Zone 4a

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

Planting Calendar

Indoor

Outdoor

Harvest

Feb 24Oct 1

Season: May 5 – Oct 1 (149 days)

Zone4a

Last FrostMay 5

First FrostOct 1

Season Length149 days

Days to Harvest120

SunFull Sun

Frost ToleranceModerate

Spacing4/sqft (6" apart)

When to Plant Leek in Zone 4a

Start Seeds Indoors: Feb 24

Start Leek seeds indoors around Feb 24 (10 weeks before last frost). Optimal germination temperature: 70°F. Germinates in 7–14 days.

Transplant Outdoors: Apr 21

Transplant Leek seedlings outdoors after Apr 21. 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 20

First harvest approximately Jul 20 (~90 days from transplant). Continue harvesting until first frost (Oct 1). Leek can overwinter in mild climates for continued harvest.

Companion Planting

✅ Carrots✅ Onions✅ Celery

❌ Beans❌ Peas

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 13b

Plan Your Leek Garden

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

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