When to Plant Kai Lan in Iron 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.
Iron County, Missouri is in USDA Zone 6b. The average last spring frost is April 16 and the first fall frost is October 21, giving you a growing season of approximately 188 days.
At an elevation of 1,227 feet, Iron County receives approximately 35.1 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Kai Lan during the growing season.
Iron County Soil Profile
Soil Type
Silt Loam
Soil pH
5.6-6.7
Drainage
Well Drained
Plant 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 Iron County
How your county's soil matches Kai Lan's growing requirements.
Soil pH
Your soil pH (5.6–6.7) overlaps with Kai Lan's range (6.0–7.5), though not a perfect match.
Soil Texture
The silt loam soil in Iron County is excellent for Kai Lan — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Kai Lan.
Organic Matter
Organic matter is moderate (3.1%). Annual compost additions will help Kai Lan.
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 22 to harvest before frost.
For a dedicated fall crop, sow by Aug 12.
Plant 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 | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.5" | 0" | ❄️ Dormant |
| Mar | — | 2.3" | 0" | ❄️ Dormant |
| Apr | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| May | 4.3" | 4" | 0.3" | 💧 Light watering |
| Jun | 4.3" | 4" | 0.3" | 💧 Light watering |
| Jul | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Aug | 4.3" | 4.1" | 0.2" | 💧 Light watering |
| Sep | 4.3" | 2.8" | 1.5" | 💧 Light watering |
| Oct | 4.3" | 3.1" | 1.2" | 💧 Light watering |
| Nov | — | 2.5" | 0" | ❄️ Dormant |
| Dec | — | 2.2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Iron 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 — Iron County, MO
Kai Lan Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 12 | Mar 12 – Mar 26 |
| Transplant Outdoors | April 16 | Apr 16 – Apr 30 |
| Direct Sow | April 2 | Apr 2 – Apr 23 |
| Harvest | June 4 | Jun 4 – Jul 2 |
| Fall Sowing | August 12 | Aug 12 – Aug 26 |
Plant 0.5" deep · 6" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | Harvest |
| July | Harvest |
| August | Fall Sowing |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1"/week · Natural rainfall sufficient
📅 Days to Maturity
45–60 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 6b
📆 Growing Season
188 days in Iron County
Growing Tips for Kai Lan in Iron County
Direct sow Kai Lan outdoors after April 16 in Iron County when soil has warmed and frost danger has passed.
Your generous 188.0-day season in Iron 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
Frequently Asked Questions
When should I plant Kai Lan in Iron County, MO?
Iron County is in Zone 6b with an average last frost of April 16. Plan your Kai Lan planting based on this frost date — see the calendar above for exact timing.
What planting zone is Iron County, MO?
Iron County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 16 and first fall frost is October 21.
Plan Your Garden with Confidence
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