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When to Plant Kai Lan in Pettis County, MO

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.

Pettis County, Missouri is in USDA Zone 6a. The average last spring frost is April 13 and the first fall frost is October 24, giving you a growing season of approximately 194 days.

At an elevation of 1,167 feet, Pettis County receives approximately 30.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87ยฐF, providing good warmth for Kai Lan during the growing season.

Pettis County, MO (Zone 6a) Moderate season
194 days
Last Spring Frost April 13
194 growing days
First Fall Frost October 24

Pettis County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-7.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (116 days to spare)
Start indoors: Mar 2 Transplant: Apr 6 🍅 Harvest: May 25 – Jun 22
Recommended (50%) ✓ Fits season (117 days to spare)
Start indoors: Mar 9 Transplant: Apr 13 🍅 Harvest: Jun 1 – Jun 29
Safe Start (90%) ✓ Fits season (112 days to spare)
Start indoors: Mar 25 Transplant: Apr 29 🍅 Harvest: Jun 17 – Jul 15

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.7″/week
You supply
0.3″/week
Watering frequency 1-2 times/week
Season total 587 gal / 100 sq ft
Kai Lan needs ~801 GDD — county provides 2,958 GDD Excellent fit

Kai Lan Planting Timeline โ€” Pettis County, MO

Kai Lan Planting Calendar

Activity When Date Range
Start Indoors March 9 Mar 9 โ€“ Mar 23
Transplant Outdoors April 13 Apr 13 โ€“ Apr 27
Direct Sow March 30 Mar 30 โ€“ Apr 20
Fall Sowing August 15 Aug 15 โ€“ Aug 29
Harvest June 1 Jun 1 โ€“ Jun 29

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

45โ€“60 days

Soil pH

6 โ€“ 7.5

USDA Zone

Zone 6a

Growing Season

194 days

Growing Tips for Pettis County

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

Frequently Asked Questions

When should I plant Kai Lan in Pettis County, MO?

Pettis County is in Zone 6a with an average last frost of April 13. Plan your Kai Lan planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Pettis County, MO?

Pettis County, Missouri is in USDA Hardiness Zone 6a. The average last spring frost is April 13 and first fall frost is October 24.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Pettis County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.

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Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Pettis County, MO. Local conditions may vary. Last updated: April 2026.