Growing Napa Cabbage in Zone 3b

Zone 3b has harsh winters and a short growing season. Start Napa Cabbage early indoors to maximize your harvest window. Last frost: May 15. First frost: Sep 22.

Planting Calendar

Indoor

Outdoor

Harvest

Apr 3Sep 22

Season: May 15 – Sep 22 (130 days)

Zone3b

Last FrostMay 15

First FrostSep 22

Season Length130 days

Days to Harvest70

SunFull Sun

Frost ToleranceModerate

Spacing12/sqft

When to Plant Napa Cabbage in Zone 3b

Start Seeds Indoors: Apr 3

Start Napa Cabbage seeds indoors around Apr 3 (6 weeks before last frost). Optimal germination temperature: 70°F. Germinates in 5–10 days.

Transplant Outdoors: Apr 24

Transplant Napa Cabbage seedlings outdoors after Apr 24. Wait until soil temperature reaches 45°F. Space plants at 12/sqft. Harden off plants for a week before moving outside.

Harvest: Jun 28

First harvest approximately Jun 28 (~65 days from transplant). Continue harvesting until first frost (Sep 22).

Fall Planting: Jun 30

For a fall harvest, plant Napa Cabbage around Jun 30 (12 weeks before first frost).

Napa Cabbage 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

Frequently Asked Questions

When should I plant Napa Cabbage in Zone 3b?

Start Napa Cabbage seeds indoors around Apr 3. Transplant outdoors after Apr 24. Expect first harvest around Jun 28.

What is the last frost date for Zone 3b?

The average last spring frost date for Zone 3b is May 15. The first fall frost averages Sep 22, giving a 130-day growing season.

Can I grow Napa Cabbage in Zone 3b?

Yes. Napa Cabbage needs 70 days to harvest. Zone 3b has a 130-day growing season, which is sufficient.

What is the best month to plant Napa Cabbage in Zone 3b?

The best time to start Napa Cabbage in Zone 3b is Apr. Begin seeds indoors around Apr 3, then transplant outdoors after the last frost date of May 15.

How long does Napa Cabbage take to harvest?

Napa Cabbage takes approximately 70 days from planting to harvest. In Zone 3b, expect your first harvest around Jun 28.

Plan Your Napa Cabbage Garden

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

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