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When to Plant Kai Lan in Freeborn County, MN

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.

Freeborn County, Minnesota is in USDA Zone 4b. The average last spring frost is May 1 and the first fall frost is October 7, giving you a growing season of approximately 159 days.

At an elevation of 1,253 feet, Freeborn County receives approximately 34.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84ยฐF, so choose short-season varieties of Kai Lan to ensure they mature before fall.

Freeborn County, MN (Zone 4b) Moderate season
159 days
Last Spring Frost May 1
159 growing days
First Fall Frost October 7

Freeborn County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-7.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (83 days to spare)
Start indoors: Mar 13 Transplant: Apr 24 🍅 Harvest: Jun 12 – Jul 10
Recommended (50%) ✓ Fits season (82 days to spare)
Start indoors: Mar 20 Transplant: May 1 🍅 Harvest: Jun 19 – Jul 17
Safe Start (90%) ✓ Fits season (77 days to spare)
Start indoors: Apr 3 Transplant: May 15 🍅 Harvest: Jul 3 – Jul 31

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
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 118 gal / 100 sq ft
Kai Lan needs ~682 GDD — county provides 2,067 GDD Excellent fit

Kai Lan Planting Timeline โ€” Freeborn County, MN

Kai Lan Planting Calendar

Activity When Date Range
Start Indoors March 20 Mar 20 โ€“ Apr 3
Transplant Outdoors May 1 May 1 โ€“ May 15
Direct Sow April 24 Apr 24 โ€“ May 15
Fall Sowing July 15 Jul 15 โ€“ Jul 29
Harvest June 19 Jun 19 โ€“ Jul 17

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

Month-by-Month Timeline

MonthActivities
January โ€”
February โ€”
March Start Indoors
April Start Indoors Direct Sow
May Transplant Outdoors Direct Sow
June Harvest
July Fall Sowing Harvest
August โ€”
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 4b

Growing Season

159 days

Growing Tips for Freeborn 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 Freeborn County, MN?

Freeborn County is in Zone 4b with an average last frost of May 1. Plan your Kai Lan planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Freeborn County, MN?

Freeborn County, Minnesota is in USDA Hardiness Zone 4b. The average last spring frost is May 1 and first fall frost is October 7.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Freeborn County gardeners in Zone 4b 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 Freeborn County, MN. Local conditions may vary. Last updated: April 2026.