When to Plant Sunflower in Brazoria County, TX
Sunflowers are tall, cheerful annuals grown for their edible seeds and as pollinator magnets. They come in sizes from 2-foot dwarfs to 12-foot giants.
Brazoria County, Texas is in USDA Zone 9a. The average last spring frost is February 12 and the first fall frost is December 8, giving you a growing season of approximately 299 days.
At an elevation of 348 feet, Brazoria County receives approximately 71.8 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 102°F, so Sunflower may need afternoon shade and extra watering during peak heat. Sandy soil warms quickly in spring — great for early planting — but Sunflower will need more frequent watering and organic matter to retain nutrients. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sunflower root diseases.
Brazoria County Soil Profile
Soil Type
Sandy Loam
Soil pH
5.5-6.3
Drainage
Well Drained
Plant Planting Risk Windows
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
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
Sunflower Planting Timeline — Brazoria County, TX
Sunflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 1 | Jan 1 – Jan 15 |
| Transplant Outdoors | February 19 | Feb 19 – Mar 5 |
| Direct Sow | February 12 | Feb 12 – Mar 5 |
| Harvest | April 30 | Apr 30 – Jun 18 |
Plant 1" deep · 18" apart · Rows 30" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Transplant Outdoors Direct Sow |
| March | Transplant Outdoors Direct Sow |
| April | Harvest |
| May | Harvest |
| June | Harvest |
| July | — |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Low — drought tolerant
Days to Maturity
70–100 days
Soil pH
6 – 7.5
USDA Zone
Zone 9a
Growing Season
299 days
Growing Tips for Brazoria County
Direct sow after last frost. Stake tall varieties in windy areas. Harvest seed heads when the back turns brown and seeds are plump. Dry heads upside down.
Companion Planting
Good Companions
Avoid Planting Near
Level Up Your Garden
Sunflower in Other Locations
Frequently Asked Questions
When should I plant Sunflower in Brazoria County, TX?
Brazoria County is in Zone 9a with an average last frost of February 12. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Brazoria County, TX?
Brazoria County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 12 and first fall frost is December 8.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Brazoria County gardeners in Zone 9a organize planting dates, track what's growing, and never miss a planting window.
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