Blog

When to Plant Napa Cabbage in USDA Zone 3a

Zone 3a Zone 3a April

Your April planting checklist for Zone 3a

April rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Zone 3a.

Avg. last frost May 19
Avg. first frost September 28
Looking ahead to May
  • Transplants going out: napa cabbage
  • Direct-sowing: napa cabbage
Get your Zone 3a-specific planner by email →

Napa cabbage forms tall, barrel-shaped heads with tender, crinkled leaves and a mild, slightly sweet flavor. It is the primary cabbage used for kimchi.

In Zone 3a, the average last spring frost is around May 15 and the first fall frost is around September 15, giving you a growing season of approximately 123 days.

Share this guide:
Facebook X
Zone 3a Short season
123 days
Last Spring Frost May 15
123 growing days
First Fall Frost September 15

Napa Cabbage Planting Timeline — Zone 3a

Where Is USDA Zone 3a?

The map below highlights the states that contain Zone 3a. Click any state to see the Napa Cabbage planting schedule for that location.

Prints a clean, ink-friendly version without maps or navigation.

Napa Cabbage Planting Calendar — Zone 3a

Activity When Date Range
Start Indoors April 3 Apr 3 – Apr 17
Transplant Outdoors May 15 May 15 – May 29
Direct Sow May 8 May 8 – May 29
Harvest July 10 Jul 10 – Aug 14
Fall Sowing June 23 Jun 23 – Jul 7

Plant 1" deep · 15" apart · Rows 24" apart

Month-by-Month Timeline

MonthActivities
January
February
March
April Start Indoors
May Transplant Outdoors Direct Sow
June Fall Sowing
July Fall Sowing Harvest
August Harvest
September
October
November
December

Free Zone 3a Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 3a with start dates, transplant windows, and harvest times.

Instant PDF download. No spam, unsubscribe any time.

Share this guide:
Facebook X

Growing Conditions

Sun

Partial Shade (3-6 hours)

💧 Water

High — keep soil consistently moist

Days to Maturity

55–75 days

Soil pH

6 – 7.5

Zone Temperature Range

°F to °F average annual minimum

Growing Season

123 days (Zone average)

Planting Specifications

Planting Depth1 inches
Plant Spacing15 inches apart
Row Spacing24 inches between rows

Succession Planting Napa Cabbage in Zone

2
successive plantings in Zone 's ~123-day season

Sow every 6.3 weeks for continuous harvest throughout the season.

Growing Tips for Napa Cabbage in Zone

Zone has a short growing season (~123 days). Start Napa Cabbage indoors early and use season-extension techniques like row covers and cold frames.

Best grown as a fall crop. Direct sow in late summer, 60-70 days before first frost. Keep soil evenly moist. Bolt-resistant varieties are available for spring planting.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries
Best Seller
The Gardener's Encyclopedia to Companion Planting

The Gardener's Encyclopedia to Companion Planting

$27 $293 value

The pairings that make vegetables, herbs, and flowers grow better — and the ones that quietly wreck a bed.

  • Proven pairings for 200+ vegetables, herbs, flowers, and fruits
  • Full seed-starting + planting schedule with timing and spacing
  • Bonus: square-foot gardening guide + printable seasonal planners
See what's inside →

Saving Napa Cabbage Seeds

Recommended for Your Garden

🌱
Seed Starting Trays $8-20

Start seeds indoors with reusable cell trays and humidity domes.

🧪
Soil Test Kit $12-25

Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.

🏷️
Garden Plant Markers $6-12

Keep your garden organized with durable, weather-resistant plant labels.

Related Plants

Frequently Asked Questions

When should I plant Napa Cabbage in Zone 3a?

In Zone 3a, plan your Napa Cabbage planting around the average last frost date of May 15. Start seeds indoors around April 3. Direct sow outdoors around May 8. Transplant seedlings around May 15.

Can Napa Cabbage grow in Zone 3a?

Yes, Napa Cabbage can grow well in Zone 3a, hardy in USDA zones 2a through 11b. Zone 3a has a growing season of approximately 123 days, which is sufficient for Napa Cabbage (55-75 days to maturity).

When can I harvest Napa Cabbage in Zone 3a?

In Zone 3a, expect to harvest Napa Cabbage from July 10 – August 14. Napa Cabbage takes 55-75 days from planting to harvest.

What is the last frost date for Zone 3a?

The average last spring frost in Zone 3a is around May 15, and the first fall frost is around September 15. This gives a growing season of approximately 123 days. These are 50% probability dates — actual frost dates vary year to year.

What should I plant next to Napa Cabbage?

Good companion plants for Napa Cabbage include Celery, Onion, Beets. These companions can help with pest control, pollination, and nutrient sharing.

🌱

Your Free Printable Garden Planner

A 24-page printable planner tailored to your zone. Planting dates, monthly task lists, harvest log, seed inventory, and succession charts — everything you need to plan a full season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Planting dates are estimates based on average frost dates — local conditions may vary. Last updated: April 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.