Napa Cabbage illustration

Growing Napa Cabbage in Zone 4b

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

Planting Calendar

Indoor
Outdoor
Harvest
Mar 20Oct 5

Season: May 1 – Oct 5 (157 days)

Zone4b
Last FrostMay 1
First FrostOct 5
Season Length157 days
Days to Harvest70
SunFull Sun
Frost ToleranceModerate
Spacing12/sqft

When to Plant Napa Cabbage in Zone 4b

Start Seeds Indoors: Mar 20

Start Napa Cabbage seeds indoors around Mar 20 (6 weeks before last frost). Optimal germination temperature: 70°F. Germinates in 5–10 days.

Transplant Outdoors: Apr 10

Transplant Napa Cabbage seedlings outdoors after Apr 10. Wait until soil temperature reaches 45°F. Space plants at 12/sqft. Harden off plants for a week before moving outside.

Harvest: Jun 14

First harvest approximately Jun 14 (~65 days from transplant). Continue harvesting until first frost (Oct 5).

Fall Planting: Jul 13

For a fall harvest, plant Napa Cabbage around Jul 13 (12 weeks before first frost).

Frequently Asked Questions

When should I plant Napa Cabbage in Zone 4b?

Start Napa Cabbage seeds indoors around Mar 20. Transplant outdoors after Apr 10. Expect first harvest around Jun 14.

What is the last frost date for Zone 4b?

The average last spring frost date for Zone 4b is May 1. The first fall frost averages Oct 5, giving a 157-day growing season.

Can I grow Napa Cabbage in Zone 4b?

Yes. Napa Cabbage needs 70 days to harvest. Zone 4b has a 157-day growing season, which is sufficient.

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

The best time to start Napa Cabbage in Zone 4b is Mar. Begin seeds indoors around Mar 20, then transplant outdoors after the last frost date of May 1.

How long does Napa Cabbage take to harvest?

Napa Cabbage takes approximately 70 days from planting to harvest. In Zone 4b, expect your first harvest around Jun 14.

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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