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When to Plant Broccoli in Callahan County, TX

Broccoli is a nutrient-dense cool-season crop that produces large central heads followed by smaller side shoots. It is one of the most popular garden vegetables.

Callahan County, Texas is in USDA Zone 7b. The average last spring frost is March 21 and the first fall frost is November 16, giving you a growing season of approximately 240 days.

At an elevation of 4,241 feet, Callahan County receives approximately 59.1 inches of rainfall annually with predominantly loam soil. Summer highs average 91ยฐF, providing good warmth for Broccoli during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Broccoli root diseases.

Callahan County, TX (Zone 7b) Long season
240 days
Last Spring Frost March 21
240 growing days
First Fall Frost November 16

Callahan County Soil Profile

Soil Type

Loam

Soil pH

6.8-7.4

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (139 days to spare)
Start indoors: Feb 3 Transplant: Mar 10 🍅 Harvest: May 12 – Jun 23
Recommended (50%) ✓ Fits season (135 days to spare)
Start indoors: Feb 14 Transplant: Mar 21 🍅 Harvest: May 23 – Jul 4
Safe Start (90%) ✓ Fits season (130 days to spare)
Start indoors: Mar 8 Transplant: Apr 12 🍅 Harvest: Jun 14 – Jul 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.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

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

Broccoli needs ~1,369 GDD — county provides 4,380 GDD Excellent fit

Broccoli Planting Timeline โ€” Callahan County, TX

Broccoli Planting Calendar

Activity When Date Range
Start Indoors February 14 Feb 14 โ€“ Feb 28
Transplant Outdoors March 21 Mar 21 โ€“ Apr 4
Direct Sow March 7 Mar 7 โ€“ Mar 28
Fall Sowing September 7 Sep 7 โ€“ Sep 21
Harvest May 23 May 23 โ€“ Jul 4

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

60โ€“90 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 7b

Growing Season

240 days

Growing Tips for Callahan County

Start seeds indoors 6-8 weeks before last frost. Provide consistent moisture to prevent hollow stems. Harvest heads before yellow flowers appear.

Companion Planting

Good Companions

Avoid Planting Near

  • Tomatoes
  • Strawberries

Level Up Your Garden

๐ŸŒพ Save Your Own Broccoli Seeds
Life Cycle Biennial
Pollination Cross-Pollinated (insects)
How to Collect Allow plants to flower 2nd year; collect dry pods.
Storage Store airtight; viable 5 years at 35ยฐF, under 50% humidity.

Isolate 1/2 mile from other brassicas. Biennial โ€” must overwinter roots.

Frequently Asked Questions

When should I plant Broccoli in Callahan County, TX?

Callahan County is in Zone 7b with an average last frost of March 21. Plan your Broccoli planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Callahan County, TX?

Callahan County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is March 21 and first fall frost is November 16.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Callahan County gardeners in Zone 7b organize planting dates, track what's growing, and never miss a planting window.

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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 Callahan County, TX. Local conditions may vary. Last updated: April 2026.