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When to Plant Cauliflower in El Paso 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.

El Paso County, Colorado is in USDA Zone 5b. The average last spring frost is May 11 and the first fall frost is October 6, giving you a growing season of approximately 148 days.

At an elevation of 8,317 feet, El Paso County receives approximately 23.5 inches of rainfall annually with predominantly loam soil. Summer highs average 87ยฐF, providing good warmth for Cauliflower during the growing season.

El Paso County, CO (Zone 5b) Short season
148 days
Last Spring Frost May 11
148 growing days
First Fall Frost October 6

El Paso County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.9

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (27 days to spare)
Start indoors: Mar 30 Transplant: May 4 🍅 Harvest: Jun 29 – Aug 31
Recommended (50%) ✓ Fits season (29 days to spare)
Start indoors: Apr 6 Transplant: May 11 🍅 Harvest: Jul 6 – Sep 7
Safe Start (90%) ✓ Fits season (24 days to spare)
Start indoors: Apr 22 Transplant: May 27 🍅 Harvest: Jul 22 – Sep 23

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.

Plant Water Budget

Plant needs
1.5″/week
Rainfall provides
0.7″/week
You supply
1.0″/week
Watering frequency 2-3 times/week
Season total 1,317 gal / 100 sq ft
Drought risk

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

Cauliflower needs ~1,182 GDD — county provides 2,257 GDD Excellent fit

Cauliflower Planting Timeline โ€” El Paso County, CO

Cauliflower Planting Calendar

Activity When Date Range
Start Indoors April 6 Apr 6 โ€“ Apr 20
Transplant Outdoors May 11 May 11 โ€“ May 25
Direct Sow April 27 Apr 27 โ€“ May 18
Fall Sowing July 28 Jul 28 โ€“ Aug 11
Harvest July 6 Jul 6 โ€“ Sep 7

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

High โ€” keep soil consistently moist

Days to Maturity

55โ€“100 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 5b

Growing Season

148 days

Growing Tips for El Paso County

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

Level Up Your Garden

Frequently Asked Questions

When should I plant Cauliflower in El Paso County, CO?

El Paso County is in Zone 5b with an average last frost of May 11. Plan your Cauliflower planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is El Paso County, CO?

El Paso County, Colorado is in USDA Hardiness Zone 5b. The average last spring frost is May 11 and first fall frost is October 6.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help El Paso County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.

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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 El Paso County, CO. Local conditions may vary. Last updated: April 2026.