Growing Napa Cabbage in Zone 3a

Zone 3a has harsh winters and a short growing season. Start Napa Cabbage early indoors to maximize your harvest window. Last frost: May 22. First frost: Sep 12.

Planting Calendar

Indoor

Outdoor

Harvest

Apr 10Sep 12

Season: May 22 – Sep 12 (113 days)

Zone3a

Last FrostMay 22

First FrostSep 12

Season Length113 days

Days to Harvest70

SunFull Sun

Frost ToleranceModerate

Spacing12/sqft

When to Plant Napa Cabbage in Zone 3a

Start Seeds Indoors: Apr 10

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

Transplant Outdoors: May 1

Transplant Napa Cabbage seedlings outdoors after May 1. Wait until soil temperature reaches 45°F. Space plants at 12/sqft. Harden off plants for a week before moving outside.

Harvest: Jul 5

First harvest approximately Jul 5 (~65 days from transplant). Continue harvesting until first frost (Sep 12).

Fall Planting: Jun 20

For a fall harvest, plant Napa Cabbage around Jun 20 (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 3a?

Start Napa Cabbage seeds indoors around Apr 10. Transplant outdoors after May 1. Expect first harvest around Jul 5.

What is the last frost date for Zone 3a?

The average last spring frost date for Zone 3a is May 22. The first fall frost averages Sep 12, giving a 113-day growing season.

Can I grow Napa Cabbage in Zone 3a?

Yes. Napa Cabbage needs 70 days to harvest. Zone 3a has a 113-day growing season, which is sufficient.

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

The best time to start Napa Cabbage in Zone 3a is Apr. Begin seeds indoors around Apr 10, then transplant outdoors after the last frost date of May 22.

How long does Napa Cabbage take to harvest?

Napa Cabbage takes approximately 70 days from planting to harvest. In Zone 3a, expect your first harvest around Jul 5.

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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