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When to Plant Cabbage in Fallon County, MT

Cabbage is a versatile cool-season crop that forms dense, leafy heads in green, red, or savoy varieties. It is a staple for coleslaw, sauerkraut, and many global cuisines.

Fallon County, Montana is in USDA Zone 4a. The average last spring frost is May 20 and the first fall frost is September 20, giving you a growing season of approximately 123 days.

At an elevation of 6,441 feet, Fallon County receives approximately 19.8 inches of rainfall annually with predominantly loam soil. Summer highs average 81ยฐF, so choose short-season varieties of Cabbage to ensure they mature before fall. With low rainfall, drip irrigation is essential for growing Cabbage successfully. Mulch heavily to conserve soil moisture.

Fallon County, MT (Zone 4a) Short season
123 days
Last Spring Frost May 20
123 growing days
First Fall Frost September 20

Fallon County Soil Profile

Soil Type

Loam

Soil pH

6.2-8.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (3 days to spare)
Start indoors: Apr 2 Transplant: May 14 🍅 Harvest: Jul 16 – Sep 10
Recommended (50%) ✓ Fits season (4 days to spare)
Start indoors: Apr 8 Transplant: May 20 🍅 Harvest: Jul 22 – Sep 16
Safe Start (90%) ✗ May not fit
Start indoors: Apr 27 Transplant: Jun 8 🍅 Harvest: Aug 10 – Oct 5

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 Fallon County

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

Soil pH

Your soil pH (6.2โ€“8.3) overlaps with Cabbage's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

The loam soil in Fallon County is excellent for Cabbage โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (2.2%). Annual compost additions will help Cabbage.

How to Plant Cabbage

1"
Planting Depth
15"
Between Plants
24"
Between Rows

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

Succession Planting Cabbage

2
successive plantings in your 123-day season

Sow every 6.9 weeks. Last sowing by Jun 12 to harvest before frost.

For a dedicated fall crop, sow by Jun 28.

Plant Water Budget

Plant needs
0.9″/week
Rainfall provides
0.7″/week
You supply
0.3″/week
Watering frequency Only during dry spells
Season total 294 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Cabbage

Cabbage needs approximately 0.9 inches of water per week (3.9" per month). Here's how your county's rainfall compares month by month.

Month Cabbage Needs Rainfall You Supplement Action
Jan โ€” 1.3" 0" โ„๏ธ Dormant
Feb โ€” 1.3" 0" โ„๏ธ Dormant
Mar โ€” 1.8" 0" โ„๏ธ Dormant
Apr โ€” 2.1" 0" โ„๏ธ Dormant
May 3.9" 2.7" 1.2" ๐Ÿ’ง Light watering
Jun 3.9" 1.4" 2.5" ๐Ÿšฟ Regular watering
Jul 3.9" 1.6" 2.3" ๐Ÿšฟ Regular watering
Aug 3.9" 1.9" 2" ๐Ÿšฟ Regular watering
Sep 3.9" 1.6" 2.3" ๐Ÿšฟ Regular watering
Oct โ€” 1.7" 0" โ„๏ธ Dormant
Nov โ€” 1.2" 0" โ„๏ธ Dormant
Dec โ€” 1.2" 0" โ„๏ธ Dormant

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

Cabbage 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" โ€” every day above 50ยฐF 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.

Cabbage needs ~860 GDD — county provides 1,322 GDD Excellent fit

Cabbage Planting Timeline โ€” Fallon County, MT

Cabbage Planting Calendar

Activity When Date Range
Start Indoors April 8 Apr 8 โ€“ Apr 22
Transplant Outdoors May 20 May 20 โ€“ Jun 3
Direct Sow May 13 May 13 โ€“ Jun 3
Harvest July 22 Jul 22 โ€“ Sep 16
Fall Sowing June 28 Jun 28 โ€“ Jul 12

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.9"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

60โ€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 4a

๐Ÿ“† Growing Season

123 days in Fallon County

Growing Tips for Cabbage in Fallon County

Direct sow Cabbage outdoors after May 20 in Fallon County when soil has warmed and frost danger has passed.

Common pests for Cabbage in this region include cabbage worm and flea beetles. Use row covers early in the season and inspect plants weekly.

Fallon County receives only 20" of rain annually. Cabbage needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Start seeds indoors 4-6 weeks before last frost. Space plants 18-24 inches apart. Keep soil evenly moist to prevent heads from splitting.

Companion Planting

Good Companions

Avoid Planting Near

  • Strawberries
  • Tomatoes

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Cabbage in Fallon County, MT?

Fallon County is in Zone 4a with an average last frost of May 20. Plan your Cabbage planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Fallon County, MT?

Fallon County, Montana is in USDA Hardiness Zone 4a. The average last spring frost is May 20 and first fall frost is September 20.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Fallon County gardeners in Zone 4a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Fallon County, MT. Local conditions may vary. Last updated: April 2026.