Blog

When to Plant Kai Lan in USDA Zone 6b

Kai lan (Chinese broccoli) is a brassica grown for its thick, glossy stems and small flower buds. It has a slightly bitter, broccoli-like flavor essential in Cantonese cooking.

In Zone 6b, the average last spring frost is around April 3 and the first fall frost is around October 25, giving you a growing season of approximately 205 days.

Zone 6b Long season
205 days
Last Spring Frost April 3
205 growing days
First Fall Frost October 25

Kai Lan Planting Timeline — Zone 6b

Where Is USDA Zone 6b?

The map below highlights the states that contain Zone 6b. Click any state to see the Kai Lan planting schedule for that location.

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

Kai Lan Planting Calendar — Zone 6b

Activity When Date Range
Start Indoors February 27 Feb 27 – Mar 13
Transplant Outdoors April 3 Apr 3 – Apr 17
Direct Sow March 20 Mar 20 – Apr 10
Harvest May 22 May 22 – Jun 19
Fall Sowing August 16 Aug 16 – Aug 30

Plant 0.5" deep · 6" apart · Rows 12" apart

Month-by-Month Timeline

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

Free Zone 6b Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 6b with start dates, transplant windows, and harvest times.

Get My Free Calendar →

Growing Conditions

Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

Days to Maturity

45–60 days

Soil pH

6 – 7.5

Zone Temperature Range

-5°F to 0°F average annual minimum

Growing Season

205 days (Zone 6b average)

Planting Specifications

Planting Depth0.5 inches
Plant Spacing6 inches apart
Row Spacing12 inches between rows

Succession Planting Kai Lan in Zone 6b

5
successive plantings in Zone 6b's ~205-day season

Sow every 5.1 weeks for continuous harvest throughout the season.

Growing Tips for Kai Lan in Zone 6b

Direct sow in spring or fall. Harvest when flower buds first appear but before they open. Cut stems at the base to encourage side shoots. Prefers cool weather.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries

Level Up Your Garden

Saving Kai Lan 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 Kai Lan in Zone 6b?

In Zone 6b, plan your Kai Lan planting around the average last frost date of April 3. Start seeds indoors around February 27. Direct sow outdoors around March 20. Transplant seedlings around April 3.

Can Kai Lan grow in Zone 6b?

Yes, Kai Lan can grow well in Zone 6b, hardy in USDA zones 2a through 11b. Zone 6b has a growing season of approximately 205 days, which is sufficient for Kai Lan (45-60 days to maturity).

When can I harvest Kai Lan in Zone 6b?

In Zone 6b, expect to harvest Kai Lan from May 22 – June 19. Kai Lan takes 45-60 days from planting to harvest.

What is the last frost date for Zone 6b?

The average last spring frost in Zone 6b is around April 3, and the first fall frost is around October 25. This gives a growing season of approximately 205 days. These are 50% probability dates — actual frost dates vary year to year.

What should I plant next to Kai Lan?

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

🌱

Plan Your Garden with Confidence

Get our free Garden Planner — organize your planting dates for Zone 6b, track your crops, and plan your garden season from seed to harvest.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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.