Blog

When to Plant Cauliflower in Ouray County, CO

Cauliflower is a cool-season brassica that produces dense white, purple, or green heads called curds. It is more finicky than broccoli but rewards with a mild, nutty flavor.

Ouray County, Colorado is in USDA Zone 5a. The average last spring frost is June 18 and the first fall frost is September 10, giving you a growing season of approximately 84 days.

At an elevation of 7,449 feet, Ouray County receives approximately 12.6 inches of rainfall annually with predominantly loam soil. Summer highs average 86ยฐF, providing good warmth for Cauliflower during the growing season. With low rainfall, drip irrigation is essential for growing Cauliflower successfully. Mulch heavily to conserve soil moisture.

Ouray County, CO (Zone 5a) Very short season
84 days
Last Spring Frost June 18
84 growing days
First Fall Frost September 10

Ouray County Soil Profile

Soil Type

Loam

Soil pH

6.4-8.3

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Apr 8 Transplant: May 13 🍅 Harvest: Jul 8 – Sep 9
Recommended (50%) ✗ May not fit
Start indoors: May 14 Transplant: Jun 18 🍅 Harvest: Aug 13 – Oct 15
Safe Start (90%) ✗ May not fit
Start indoors: May 25 Transplant: Jun 29 🍅 Harvest: Aug 24 – Oct 26

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 Ouray County

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

Soil pH

Your soil pH (6.4โ€“8.3) is more alkaline than Cauliflower prefers (6.0โ€“7.0). Add sulfur or peat moss to lower pH.

Soil Texture

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

Organic Matter

Organic matter is moderate (2.7%). Annual compost additions will help Cauliflower.

How to Plant Cauliflower

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

Fall planting: Sow 10 weeks before your first frost date for a fall harvest.

How Much Cauliflower to Grow

1-2 lbs
Average yield per plant
3
Plants per person
7.5 sq ft
Space per person

For a family of 4, plant approximately 12 cauliflower plants in about 30 sq ft. In Ouray County's 84-day season, you'll have plenty of time for a full harvest. Plan your garden layout →

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.6″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 332 gal / 100 sq ft
Drought risk

Water stress score is 8/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Cauliflower

Cauliflower needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Cauliflower Needs Rainfall You Supplement Action
Jan โ€” 0.8" 0" โ„๏ธ Dormant
Feb โ€” 0.7" 0" โ„๏ธ Dormant
Mar โ€” 1" 0" โ„๏ธ Dormant
Apr โ€” 1.4" 0" โ„๏ธ Dormant
May โ€” 1.3" 0" โ„๏ธ Dormant
Jun 4.3" 1" 3.3" ๐Ÿšฟ Regular watering
Jul 4.3" 1.2" 3.1" ๐Ÿšฟ Regular watering
Aug 4.3" 1.4" 2.9" ๐Ÿšฟ Regular watering
Sep 4.3" 1.1" 3.2" ๐Ÿšฟ Regular watering
Oct โ€” 1" 0" โ„๏ธ Dormant
Nov โ€” 1" 0" โ„๏ธ Dormant
Dec โ€” 0.7" 0" โ„๏ธ Dormant

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

Cauliflower 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.

Cauliflower needs ~1,124 GDD — county provides 1,218 GDD Good fit

Cauliflower Planting Timeline โ€” Ouray County, CO

Cauliflower Planting Calendar

Activity When Date Range
Start Indoors May 14 May 14 โ€“ May 28
Transplant Outdoors June 18 Jun 18 โ€“ Jul 2
Direct Sow June 4 Jun 4 โ€“ Jun 25
Harvest August 13 Aug 13 โ€“ Oct 15
Fall Sowing July 2 Jul 2 โ€“ Jul 16

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท 1-2 times/week

๐Ÿ“… Days to Maturity

55โ€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: too_alkaline

๐Ÿ—บ๏ธ USDA Zone

Zone 5a

๐Ÿ“† Growing Season

84 days in Ouray County

Growing Tips for Cauliflower in Ouray County

Direct sow Cauliflower outdoors after June 18 in Ouray County when soil has warmed and frost danger has passed.

Your 84.0-day growing season in Ouray County is tight for Cauliflower (55.0-100.0 days to maturity). Start indoors and choose early-maturing varieties.

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

Ouray County receives only 13" of rain annually. Cauliflower needs consistent moisture โ€” install drip irrigation or water deeply 2-3 times per week.

General growing tips

Start seeds indoors 6 weeks before transplanting. Blanch white varieties by tying outer leaves over the head. Provide consistent moisture and avoid temperature extremes.

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 Cauliflower in Ouray County, CO?

Ouray County is in Zone 5a with an average last frost of June 18. Plan your Cauliflower planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Ouray County, CO?

Ouray County, Colorado is in USDA Hardiness Zone 5a. The average last spring frost is June 18 and first fall frost is September 10.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Ouray County gardeners in Zone 5a 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 Ouray County, CO. Local conditions may vary. Last updated: April 2026.