Napa Cabbage illustration

Growing Napa Cabbage in Zone 4a

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

Planting Calendar

Indoor
Outdoor
Harvest
Mar 24Oct 1

Season: May 5 – Oct 1 (149 days)

Zone4a
Last FrostMay 5
First FrostOct 1
Season Length149 days
Days to Harvest70
SunFull Sun
Frost ToleranceModerate
Spacing12/sqft

When to Plant Napa Cabbage in Zone 4a

Start Seeds Indoors: Mar 24

Start Napa Cabbage seeds indoors around Mar 24 (6 weeks before last frost). Optimal germination temperature: 70°F. Germinates in 5–10 days.

Transplant Outdoors: Apr 14

Transplant Napa Cabbage seedlings outdoors after Apr 14. Wait until soil temperature reaches 45°F. Space plants at 12/sqft. Harden off plants for a week before moving outside.

Harvest: Jun 18

First harvest approximately Jun 18 (~65 days from transplant). Continue harvesting until first frost (Oct 1).

Fall Planting: Jul 9

For a fall harvest, plant Napa Cabbage around Jul 9 (12 weeks before first frost).

Frequently Asked Questions

When should I plant Napa Cabbage in Zone 4a?

Start Napa Cabbage seeds indoors around Mar 24. Transplant outdoors after Apr 14. Expect first harvest around Jun 18.

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 Napa Cabbage in Zone 4a?

Yes. Napa Cabbage needs 70 days to harvest. Zone 4a has a 149-day growing season, which is sufficient.

What is the best month to plant Napa Cabbage in Zone 4a?

The best time to start Napa Cabbage in Zone 4a is Mar. Begin seeds indoors around Mar 24, then transplant outdoors after the last frost date of May 5.

How long does Napa Cabbage take to harvest?

Napa Cabbage takes approximately 70 days from planting to harvest. In Zone 4a, expect your first harvest around Jun 18.

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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