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When to Plant Kai Lan in Loudoun County, VA

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.

Loudoun County, Virginia is in USDA Zone 7a. The average last spring frost is April 18 and the first fall frost is October 19, giving you a growing season of approximately 184 days.

At an elevation of 857 feet, Loudoun County receives approximately 45.8 inches of rainfall annually with predominantly silt loam soil. Summer highs average 94ยฐF, providing good warmth for Kai Lan during the growing season.

Loudoun County, VA (Zone 7a) Moderate season
184 days
Last Spring Frost April 18
184 growing days
First Fall Frost October 19

Loudoun County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-6.5

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 โ€” 3.5" 0" โ„๏ธ Dormant
Feb โ€” 3.4" 0" โ„๏ธ Dormant
Mar โ€” 4" 0" โ„๏ธ Dormant
Apr 4.3" 4" 0.3" ๐Ÿ’ง Light watering
May 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
Jun 4.3" 4.7" 0" โœ… Rainfall sufficient
Jul 4.3" 4.4" 0" โœ… Rainfall sufficient
Aug 4.3" 4.6" 0" โœ… Rainfall sufficient
Sep 4.3" 3.3" 1" ๐Ÿ’ง Light watering
Oct 4.3" 3.4" 0.9" ๐Ÿ’ง Light watering
Nov โ€” 3.5" 0" โ„๏ธ Dormant
Dec โ€” 3.9" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Loudoun County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Kai Lan Planting Timeline โ€” Loudoun County, VA

Kai Lan Planting Calendar

Activity When Date Range
Start Indoors March 14 Mar 14 โ€“ Mar 28
Transplant Outdoors April 18 Apr 18 โ€“ May 2
Direct Sow April 4 Apr 4 โ€“ Apr 25
Harvest June 6 Jun 6 โ€“ Jul 4
Fall Sowing August 10 Aug 10 โ€“ Aug 24

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 Transplant Outdoors
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

Moderate โ€” regular watering

๐Ÿ“… Days to Maturity

45โ€“60 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: N/A

๐Ÿ—บ๏ธ USDA Zone

Zone 7a

๐Ÿ“† Growing Season

184 days in Loudoun County

Growing Tips for Loudoun 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 Loudoun County, VA?

Loudoun County is in Zone 7a with an average last frost of April 18. Plan your Kai Lan planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Loudoun County, VA?

Loudoun County, Virginia is in USDA Hardiness Zone 7a. The average last spring frost is April 18 and first fall frost is October 19.

๐ŸŒฑ

Plan Your Garden with Confidence

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