When to plant Kai Lan in Walnut, IL
In Walnut, plant Kai Lan in spring between April 8 and April 29, once soil temps hold above 50°F. Walnut's last frost averages April 22, so time plantings around the expected last-frost window for best survival. For a fall crop, sow between August 5 and August 19 — roughly 45–60 days before the first frost on October 14.
When to Plant Kai Lan in Walnut, IL
Your June planting checklist for Bureau County, Illinois
Here's what deserves your attention in Bureau County, Illinois this month. Everything below is tailored to Zone 5b and timed around your local frost dates.
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.
Walnut, Illinois is in USDA Zone 5b. The average last spring frost is April 22 and the first fall frost is October 14, giving you a growing season of approximately 175 days.
At an elevation of 613 feet, Bureau County receives approximately 34.9 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.
Walnut Soil Profile
Soil Type
Silt Loam
Soil pH
6.3-6.7
Drainage
Well Drained
Kai Lan Planting Risk Windows
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.
Soil Compatibility in Walnut
How your county's soil matches Kai Lan's growing requirements.
Soil pH
Your soil pH (6.3–6.7) is within Kai Lan's preferred range (6.0–7.5).
Soil Texture
The silt loam soil in Bureau County is excellent for Kai Lan — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is excellent (4.1%) — Kai Lan will thrive.
How to Plant Kai Lan
Fall planting: Sow 10 weeks before your first frost date for a fall harvest.
Succession Planting Kai Lan
Sow every 5.1 weeks. Last sowing by Aug 15 to harvest before frost.
For a dedicated fall crop, sow by Aug 05.
Kai Lan Water Budget
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 | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.6" | 0" | ❄️ Dormant |
| Mar | — | 2.2" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.2" | 1.1" | 💧 Light watering |
| May | 4.3" | 4.4" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 4.7" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 4" | 0.3" | 💧 Light watering |
| Aug | 4.3" | 3.3" | 1" | 💧 Light watering |
| Sep | 4.3" | 2.8" | 1.5" | 💧 Light watering |
| Oct | 4.3" | 2.7" | 1.6" | 💧 Light watering |
| Nov | — | 2.6" | 0" | ❄️ Dormant |
| Dec | — | 1.7" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Bureau County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Kai Lan Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Kai Lan Planting Timeline — Walnut, IL
Kai Lan Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 18 | Mar 18 – Apr 1 |
| Transplant Outdoors | April 22 | Apr 22 – May 6 |
| Direct Sow | April 8 | Apr 8 – Apr 29 |
| Harvest | June 10 | Jun 10 – Jul 8 |
| Fall Sowing | August 5 | Aug 5 – Aug 19 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Start Indoors Transplant Outdoors Direct Sow |
| May | Transplant Outdoors |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Only during dry spells
📅 Days to Maturity
45–60 days
🧪 Soil pH
Needs 6–7.5 · Your soil: ideal
🗺️ USDA Zone
Zone 5b
📆 Growing Season
175 days in Bureau County
Growing Tips for Kai Lan in Walnut
Direct sow Kai Lan outdoors after April 22 in Bureau County when soil has warmed and frost danger has passed.
Your generous 175.0-day season in Bureau County allows multiple plantings of Kai Lan. Sow every 22.0 days for continuous harvest.
Common pests for Kai Lan in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
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
Check more plant combinations with our Companion Planting Checker →
Kai Lan in Other Locations
When should I plant Kai Lan in Walnut, IL?
In Walnut, IL, plant Kai Lan after the last frost (around April 22) and before the first frost (around October 14). Best results when soil holds above 50°F.
What growing zone is Walnut, IL for Kai Lan?
Walnut 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 Walnut's climate?
Yes — Kai Lan grows well in Walnut's temperate climate. Walnut averages a 175-day frost-free season, with last frost around April 22 and first frost around October 14.
Your Bureau County Garden Planner — Free
A 22-page printable planner built for Bureau 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.