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When to Plant Kai Lan in Grainger 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.

Grainger County, Tennessee is in USDA Zone 7a. The average last spring frost is April 15 and the first fall frost is October 22, giving you a growing season of approximately 190 days.

At an elevation of 3,009 feet, Grainger County receives approximately 49.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 92ยฐF, providing good warmth for Kai Lan during the growing season.

Grainger County, TN (Zone 7a) Moderate season
190 days
Last Spring Frost April 15
190 growing days
First Fall Frost October 22

Grainger County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (116 days to spare)
Start indoors: Mar 4 Transplant: Apr 8 🍅 Harvest: May 27 – Jun 24
Recommended (50%) ✓ Fits season (113 days to spare)
Start indoors: Mar 11 Transplant: Apr 15 🍅 Harvest: Jun 3 – Jul 1
Safe Start (90%) ✓ Fits season (108 days to spare)
Start indoors: Mar 28 Transplant: May 2 🍅 Harvest: Jun 20 – Jul 18

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.

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
Kai Lan needs ~998 GDD — county provides 3,610 GDD Excellent fit

Kai Lan Planting Timeline โ€” Grainger 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
Fall Sowing August 13 Aug 13 โ€“ Aug 27
Harvest June 3 Jun 3 โ€“ Jul 1

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

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

45โ€“60 days

Soil pH

6 โ€“ 7.5

USDA Zone

Zone 7a

Growing Season

190 days

Growing Tips for Grainger 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

Level Up Your Garden

Frequently Asked Questions

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

Grainger 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 Grainger County, TN?

Grainger County, Tennessee is in USDA Hardiness Zone 7a. The average last spring frost is April 15 and first fall frost is October 22.

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Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Grainger 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 Grainger County, TN. Local conditions may vary. Last updated: April 2026.