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When to plant Kai Lan in Madison County, IA

In Madison County, plant Kai Lan in spring between April 10 and May 1, once soil temps hold above 50°F. Madison County's last frost averages April 24, so time plantings around the expected last-frost window for best survival. For a fall crop, sow between August 2 and August 16 — roughly 45–60 days before the first frost on October 11.

When to Plant Kai Lan in Madison County, IA

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.

Madison County, Iowa is in USDA Zone 5b. The average last spring frost is April 24 and the first fall frost is October 11, giving you a growing season of approximately 170 days.

At an elevation of 1,022 feet, Madison County receives approximately 40.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 84°F, so choose short-season varieties of Kai Lan to ensure they mature before fall.

Madison County, IA (Zone 5b) Moderate season
170 days
Last Spring Frost April 24
170 growing days
First Fall Frost October 11

Madison County Soil Profile

Soil Type

Silt Loam

Soil pH

6.0-7.0

Drainage

Well Drained

Kai Lan Planting Timeline — Madison County, IA

Kai Lan Planting Calendar

Activity When Date Range
Start Indoors March 20 Mar 20 – Apr 3
Transplant Outdoors April 24 Apr 24 – May 8
Direct Sow April 10 Apr 10 – May 1
Harvest June 12 Jun 12 – Jul 10
Fall Sowing August 2 Aug 2 – Aug 16

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

45–60 days

🧪 Soil pH

Needs 6–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 5b

📆 Growing Season

170 days in Madison County

Growing Tips for Madison 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

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Kai Lan in Madison County, IA?

Madison County is in Zone 5b with an average last frost of April 24. Plan your Kai Lan planting based on this frost date — see the calendar above for exact timing.

What planting zone is Madison County, IA?

Madison County, Iowa is in USDA Hardiness Zone 5b. The average last spring frost is April 24 and first fall frost is October 11.

When should I plant Kai Lan in Madison County, IA?

In Madison County, IA, plant Kai Lan after the last frost (around April 24) and before the first frost (around October 11). Best results when soil holds above 50°F.

What growing zone is Madison County, IA for Kai Lan?

Madison County sits in USDA Zone 5b. Kai Lan grows reliably in zones 2a through 11b, so it's a good fit here.

Can Kai Lan grow in Madison County's climate?

Yes — Kai Lan grows well in Madison County's temperate climate. Madison County averages a 170-day frost-free season, with last frost around April 24 and first frost around October 11.

🌱

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A 22-page printable planner built for Madison County (Zone 5b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Madison County, IA. Local conditions may vary. Last updated: June 2026.

Sources & credits

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