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When to Plant Kai Lan in Castleton, VT

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.

Castleton, Vermont is in USDA Zone 5a. The average last spring frost is May 9 and the first fall frost is October 7, giving you a growing season of approximately 151 days.

At an elevation of 477 feet, Rutland County receives approximately 41.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81°F, so choose short-season varieties of Kai Lan to ensure they mature before fall.

Castleton, VT (Zone 5a) Moderate season
151 days
Last Spring Frost May 9
151 growing days
First Fall Frost October 7

Castleton Soil Profile

Soil Type

Silt Loam

Soil pH

5.1-6.3

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 3.1" 0" ❄️ Dormant
Feb 2.4" 0" ❄️ Dormant
Mar 3.6" 0" ❄️ Dormant
Apr 3.7" 0" ❄️ Dormant
May 4.3" 3.9" 0.4" 💧 Light watering
Jun 4.3" 4.1" 0.2" 💧 Light watering
Jul 4.3" 4" 0.3" 💧 Light watering
Aug 4.3" 3.5" 0.8" 💧 Light watering
Sep 4.3" 3.8" 0.5" 💧 Light watering
Oct 4.3" 3" 1.3" 💧 Light watering
Nov 3.4" 0" ❄️ Dormant
Dec 3.3" 0" ❄️ Dormant

Water needs are for active growing months only (May–Oct in Rutland County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Kai Lan Planting Timeline — Castleton, VT

Kai Lan Planting Calendar

Activity When Date Range
Start Indoors April 4 Apr 4 – Apr 18
Transplant Outdoors May 9 May 9 – May 23
Direct Sow April 25 Apr 25 – May 16
Harvest June 27 Jun 27 – Jul 25
Fall Sowing July 29 Jul 29 – Aug 12

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

45–60 days

🧪 Soil pH

Needs 6–7.5 · Your soil: N/A

🗺️ USDA Zone

Zone 5a

📆 Growing Season

151 days in Rutland County

Growing Tips for Castleton

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 →

🌱

Your Rutland County Garden Planner — Free

A 22-page printable planner built for Rutland County (Zone 5a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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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 Rutland County, VT. Local conditions may vary. Last updated: July 2026.