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When to Plant Kohlrabi in Daniels County, MT

Daniels County, Montana Zone 3b May

Top priorities for Daniels County, Montana gardeners in May

May rewards gardeners who work with the weather, not against it. Here's how to stay in step this month in Daniels County, Montana.

Avg. last frost May 20
Avg. first frost September 16
Soil temp (4") 33°F
Watering High
Pest pressure Low
Daylight 15 hrs
  1. Get kohlrabi in the ground

    Water the tray well an hour before you transplant. Roots slide out cleanly and settle in faster.

  2. Put kohlrabi seeds straight in the ground

    Thin ruthlessly once seedlings are up. Crowded roots mean smaller crops from every plant.

Coming up in June — start thinking about
  • Fall sowing: 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.

Daniels County, Montana is in USDA Zone 3b. The average last spring frost is May 20 and the first fall frost is September 16, giving you a growing season of approximately 119 days.

At an elevation of 6,023 feet, Daniels County receives approximately 15.5 inches of rainfall annually with predominantly loam soil. Summer highs average 78°F, so choose short-season varieties of Kohlrabi to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Kohlrabi successfully. Mulch heavily to conserve soil moisture.

Daniels County, MT (Zone 3b) Short season
119 days
Last Spring Frost May 20
119 growing days
First Fall Frost September 16

Daniels County Soil Profile

Soil Type

Loam

Soil pH

6.3-7.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (33 days to spare)
Start indoors: Apr 2 Transplant: May 14 🍅 Harvest: Jul 2 – Aug 6
Recommended (50%) ✓ Fits season (35 days to spare)
Start indoors: Apr 8 Transplant: May 20 🍅 Harvest: Jul 8 – Aug 12
Safe Start (90%) ✓ Fits season (27 days to spare)
Start indoors: Apr 28 Transplant: Jun 9 🍅 Harvest: Jul 28 – Sep 1

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 Daniels County

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

Soil pH

Your soil pH (6.3–7.8) overlaps with Kohlrabi's range (6.0–7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.3%). 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 119-day season

Sow every 5.1 weeks. Last sowing by Jul 13 to harvest before frost.

For a dedicated fall crop, sow by Jun 24.

Plant Water Budget

Plant needs
0.7″/week
Rainfall provides
0.6″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 194 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 1" 0" ❄️ Dormant
Feb 0.8" 0" ❄️ Dormant
Mar 1.5" 0" ❄️ Dormant
Apr 1.7" 0" ❄️ Dormant
May 3" 1.9" 1.1" 💧 Light watering
Jun 3" 1.1" 1.9" 🚿 Regular watering
Jul 3" 1.2" 1.8" 🚿 Regular watering
Aug 3" 1.6" 1.4" 💧 Light watering
Sep 3" 1.3" 1.7" 🚿 Regular watering
Oct 1.3" 0" ❄️ Dormant
Nov 1.1" 0" ❄️ Dormant
Dec 0.9" 0" ❄️ Dormant

Water needs are for active growing months only (May–Sep in Daniels 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 ~468 GDD — county provides 1,011 GDD Excellent fit

Kohlrabi Planting Timeline — Daniels County, MT

Kohlrabi Planting Calendar

Activity When Date Range
Start Indoors April 8 Apr 8 – Apr 22
Transplant Outdoors May 20 May 20 – Jun 3
Direct Sow May 13 May 13 – Jun 3
Harvest July 8 Jul 8 – Aug 12
Fall Sowing June 24 Jun 24 – Jul 8

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 Transplant Outdoors Direct Sow Fall Sowing
July Fall Sowing Harvest
August Harvest
September
October
November
December

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

0.7"/week · Only during dry spells

📅 Days to Maturity

45–65 days

🧪 Soil pH

Needs 6–7.5 · Your soil: acceptable

🗺️ USDA Zone

Zone 3b

📆 Growing Season

119 days in Daniels County

Growing Tips for Kohlrabi in Daniels County

Direct sow Kohlrabi outdoors after May 20 in Daniels 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 Daniels County, MT?

Daniels County is in Zone 3b with an average last frost of May 20. Plan your Kohlrabi planting based on this frost date — see the calendar above for exact timing.

What planting zone is Daniels County, MT?

Daniels County, Montana is in USDA Hardiness Zone 3b. The average last spring frost is May 20 and first fall frost is September 16.

🌱

Your Daniels County Garden Planner — Free

A 24-page printable planner built for Daniels County (Zone 3b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Daniels County, MT. 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.