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When to Plant Kai Lan in Cumberland County, TN

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.

Cumberland County, Tennessee is in USDA Zone 7a. The average last spring frost is April 15 and the first fall frost is October 23, giving you a growing season of approximately 191 days.

At an elevation of 3,392 feet, Cumberland County receives approximately 50.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 94ยฐF, providing good warmth for Kai Lan during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Kai Lan root diseases.

Cumberland County, TN (Zone 7a) Moderate season
191 days
Last Spring Frost April 15
191 growing days
First Fall Frost October 23

Cumberland County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (115 days to spare)
Start indoors: Mar 4 Transplant: Apr 8 🍅 Harvest: May 27 – Jun 24
Recommended (50%) ✓ Fits season (114 days to spare)
Start indoors: Mar 11 Transplant: Apr 15 🍅 Harvest: Jun 3 – Jul 1
Safe Start (90%) ✓ Fits season (111 days to spare)
Start indoors: Mar 25 Transplant: Apr 29 🍅 Harvest: Jun 17 – Jul 15

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 Cumberland County

How your county's soil matches Kai Lan's growing requirements.

Soil pH

Your soil pH (5.5โ€“7.0) overlaps with Kai Lan's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The silt loam soil in Cumberland County is excellent for Kai Lan โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.8%). Annual compost additions will help Kai Lan.

How to Plant Kai Lan

0.5"
Planting Depth
6"
Between Plants
12"
Between Rows

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

Succession Planting Kai Lan

5
successive plantings in your 191-day season

Sow every 5.1 weeks. Last sowing by Aug 24 to harvest before frost.

For a dedicated fall crop, sow by Aug 14.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

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 โ€” 4.3" 0" โ„๏ธ Dormant
Feb โ€” 3.7" 0" โ„๏ธ Dormant
Mar โ€” 5.5" 0" โ„๏ธ Dormant
Apr 4.3" 3.9" 0.4" ๐Ÿ’ง Light watering
May 4.3" 4.3" 0" โœ… Rainfall sufficient
Jun 4.3" 4.4" 0" โœ… Rainfall sufficient
Jul 4.3" 5" 0" โœ… Rainfall sufficient
Aug 4.3" 4.3" 0" โœ… Rainfall sufficient
Sep 4.3" 4.4" 0" โœ… Rainfall sufficient
Oct 4.3" 2.9" 1.4" ๐Ÿ’ง Light watering
Nov โ€” 4.3" 0" โ„๏ธ Dormant
Dec โ€” 3.6" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Cumberland County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 needs ~1,076 GDD — county provides 3,915 GDD Excellent fit

Kai Lan Planting Timeline โ€” Cumberland County, TN

Kai Lan Planting Calendar

Activity When Date Range
Start Indoors March 11 Mar 11 โ€“ Mar 25
Transplant Outdoors April 15 Apr 15 โ€“ Apr 29
Direct Sow April 1 Apr 1 โ€“ Apr 22
Harvest June 3 Jun 3 โ€“ Jul 1
Fall Sowing August 14 Aug 14 โ€“ Aug 28

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

45โ€“60 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

191 days in Cumberland County

Growing Tips for Kai Lan in Cumberland County

Direct sow Kai Lan outdoors after April 15 in Cumberland County when soil has warmed and frost danger has passed.

Your generous 191.0-day season in Cumberland 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

  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Kai Lan in Cumberland County, TN?

Cumberland County is in Zone 7a with an average last frost of April 15. Plan your Kai Lan planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Cumberland County, TN?

Cumberland County, Tennessee is in USDA Hardiness Zone 7a. The average last spring frost is April 15 and first fall frost is October 23.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Cumberland County gardeners in Zone 7a 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 Cumberland County, TN. Local conditions may vary. Last updated: April 2026.