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When to Plant Kohlrabi in Caledonia County, VT

Caledonia County, Vermont Zone 4b May

May in the garden — Caledonia County, Vermont

Welcome to May in Zone 4b. These are the moves that will have the biggest impact on your growing season.

Avg. last frost May 14
Avg. first frost October 3
Soil temp (4") 54°F
Watering Low
Pest pressure Low
Daylight 14.6 hrs
  1. Set out kohlrabi seedlings

    Plant tomatoes deep — bury the stem up to the first true leaves to grow extra roots. Everything else goes in at the same depth it grew in the tray.

  2. Plant kohlrabi from seed, right in the garden

    Your soil is 54°F — warm enough for these to germinate without babying.

Before June arrives, get these ready
  • Starting indoors: kohlrabi

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Kohlrabi is an unusual brassica that forms a swollen stem above ground with a mild, sweet turnip-like flavor. Both the bulb and tender leaves are edible.

Caledonia County, Vermont is in USDA Zone 4b. The average last spring frost is May 14 and the first fall frost is October 3, giving you a growing season of approximately 142 days.

At an elevation of 1,052 feet, Caledonia County receives approximately 49.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82°F, so choose short-season varieties of Kohlrabi to ensure they mature before fall.

Caledonia County, VT (Zone 4b) Short season
142 days
Last Spring Frost May 14
142 growing days
First Fall Frost October 3

Caledonia County Soil Profile

Soil Type

Silt Loam

Soil pH

5-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (57 days to spare)
Start indoors: Mar 27 Transplant: May 8 🍅 Harvest: Jun 26 – Jul 31
Recommended (50%) ✓ Fits season (58 days to spare)
Start indoors: Apr 2 Transplant: May 14 🍅 Harvest: Jul 2 – Aug 6
Safe Start (90%) ✓ Fits season (61 days to spare)
Start indoors: Apr 15 Transplant: May 27 🍅 Harvest: Jul 15 – Aug 19

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 Caledonia County

How your county's soil matches Kohlrabi's growing requirements.

Soil pH

Your soil pH (5.0–6.8) is more acidic than Kohlrabi prefers (6.0–7.5). Add garden lime to raise pH.

Soil Texture

The silt loam soil in Caledonia County is excellent for Kohlrabi — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.9%). Annual compost additions will help Kohlrabi.

How to Plant Kohlrabi

0.5"
Planting Depth
4"
Between Plants
12"
Between Rows

Fall planting: Sow 12 weeks before your first frost date for a fall harvest.

Succession Planting Kohlrabi

3
successive plantings in your 142-day season

Sow every 5.1 weeks. Last sowing by Jul 30 to harvest before frost.

For a dedicated fall crop, sow by Jul 11.

Plant Water Budget

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

Monthly Watering Guide for Kohlrabi

Kohlrabi needs approximately 0.7 inches of water per week (3" per month). Here's how your county's rainfall compares month by month.

Month Kohlrabi Needs Rainfall You Supplement Action
Jan 3.4" 0" ❄️ Dormant
Feb 3.3" 0" ❄️ Dormant
Mar 4.7" 0" ❄️ Dormant
Apr 4.1" 0" ❄️ Dormant
May 3" 4.4" 0" ✅ Rainfall sufficient
Jun 3" 5.1" 0" ✅ Rainfall sufficient
Jul 3" 4.9" 0" ✅ Rainfall sufficient
Aug 3" 5" 0" ✅ Rainfall sufficient
Sep 3" 3.8" 0" ✅ Rainfall sufficient
Oct 3" 4.4" 0" ✅ Rainfall sufficient
Nov 3.4" 0" ❄️ Dormant
Dec 3.1" 0" ❄️ Dormant

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

Kohlrabi 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.

Kohlrabi needs ~632 GDD — county provides 1,633 GDD Excellent fit

Kohlrabi Planting Timeline — Caledonia County, VT

Kohlrabi Planting Calendar

Activity When Date Range
Start Indoors April 2 Apr 2 – Apr 16
Transplant Outdoors May 14 May 14 – May 28
Direct Sow May 7 May 7 – May 28
Harvest July 2 Jul 2 – Aug 6
Fall Sowing July 11 Jul 11 – Jul 25

Plant 0.5" deep · 4" apart · Rows 12" apart

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.7"/week · Natural rainfall sufficient

📅 Days to Maturity

45–65 days

🧪 Soil pH

Needs 6–7.5 · Your soil: too_acidic

🗺️ USDA Zone

Zone 4b

📆 Growing Season

142 days in Caledonia County

Growing Tips for Kohlrabi in Caledonia County

Direct sow Kohlrabi outdoors after May 14 in Caledonia County when soil has warmed and frost danger has passed.

Common pests for Kohlrabi 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 bulbs are 2-3 inches in diameter for best texture and flavor. Larger bulbs may become woody and fibrous.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Strawberries

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Kohlrabi in Caledonia County, VT?

Caledonia County is in Zone 4b with an average last frost of May 14. Plan your Kohlrabi planting based on this frost date — see the calendar above for exact timing.

What planting zone is Caledonia County, VT?

Caledonia County, Vermont is in USDA Hardiness Zone 4b. The average last spring frost is May 14 and first fall frost is October 3.

🌱

Your Caledonia County Garden Planner — Free

A 24-page printable planner built for Caledonia County (Zone 4b). 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 Caledonia County, VT. Local conditions may vary. Last updated: May 2026.

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.