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When to plant Kai Lan in Randolph County, IL

Randolph County gardeners should plant Kai Lan between March 28 and April 18 in spring. With Randolph County's Zone 7a climate (last frost April 11), Kai Lan needs 45–60 days to mature — plant by August 21 for a full harvest. A second sowing from August 11 to August 25 extends the harvest into fall.

When to Plant Kai Lan in Randolph County, IL

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.

Randolph County, Illinois is in USDA Zone 7a. The average last spring frost is April 11 and the first fall frost is October 20, giving you a growing season of approximately 192 days.

At an elevation of 501 feet, Randolph County receives approximately 32.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Kai Lan during the growing season.

Randolph County, IL (Zone 7a) Moderate season
192 days
Last Spring Frost April 11
192 growing days
First Fall Frost October 20

Randolph County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.8

Drainage

Well Drained

Monthly Watering Guide for Kai Lan

Kai Lan needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Kai Lan Needs Rainfall You Supplement Action
Jan 1.2" 0" ❄️ Dormant
Feb 1.3" 0" ❄️ Dormant
Mar 2.4" 0" ❄️ Dormant
Apr 4.3" 3.2" 1.1" 💧 Light watering
May 4.3" 4.1" 0.2" 💧 Light watering
Jun 4.3" 4.3" 0" ✅ Rainfall sufficient
Jul 4.3" 3.6" 0.7" 💧 Light watering
Aug 4.3" 3" 1.3" 💧 Light watering
Sep 4.3" 3.2" 1.1" 💧 Light watering
Oct 4.3" 2.4" 1.9" 💧 Light watering
Nov 2.2" 0" ❄️ Dormant
Dec 1.8" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Randolph County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Kai Lan Planting Timeline — Randolph County, IL

Kai Lan Planting Calendar

Activity When Date Range
Start Indoors March 7 Mar 7 – Mar 21
Transplant Outdoors April 11 Apr 11 – Apr 25
Direct Sow March 28 Mar 28 – Apr 18
Harvest May 30 May 30 – Jun 27
Fall Sowing August 11 Aug 11 – Aug 25

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

Month-by-Month Timeline

MonthActivities
January
February
March Start Indoors Direct Sow
April Transplant Outdoors Direct Sow
May Harvest
June Harvest
July
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 7a

📆 Growing Season

192 days in Randolph County

Growing Tips for Randolph 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 Randolph County, IL?

Randolph County is in Zone 7a with an average last frost of April 11. Plan your Kai Lan planting based on this frost date — see the calendar above for exact timing.

What planting zone is Randolph County, IL?

Randolph County, Illinois is in USDA Hardiness Zone 7a. The average last spring frost is April 11 and first fall frost is October 20.

When should I plant Kai Lan in Randolph County, IL?

In Randolph County, IL, plant Kai Lan after the last frost (around April 11) and before the first frost (around October 20). Best results when soil holds above 50°F.

What growing zone is Randolph County, IL for Kai Lan?

Randolph County sits in USDA Zone 7a. Kai Lan grows reliably in zones 2a through 11b, so it's a good fit here.

Can Kai Lan grow in Randolph County's climate?

Yes — Kai Lan grows well in Randolph County's temperate climate. Randolph County averages a 192-day frost-free season, with last frost around April 11 and first frost around October 20.

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Your Randolph County Garden Planner — Free

A 22-page printable planner built for Randolph County (Zone 7a). 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 Randolph County, IL. Local conditions may vary. Last updated: June 2026.

Sources & credits

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