When to Plant Sunflower in Grimes 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.
Grimes County, Texas is in USDA Zone 8b. The average last spring frost is February 25 and the first fall frost is December 1, giving you a growing season of approximately 279 days.
At an elevation of 33 feet, Grimes County receives approximately 65.2 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 91°F, providing good warmth for Sunflower during the growing season. 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.
Grimes County Soil Profile
Soil Type
Sandy Loam
Soil pH
5.8-6.5
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 — Grimes County, TX
Sunflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 7 | Jan 7 – Jan 21 |
| Transplant Outdoors | March 11 | Mar 11 – Mar 25 |
| Direct Sow | March 4 | Mar 4 – Mar 25 |
| Harvest | May 20 | May 20 – Jul 8 |
Plant 1" deep · 18" apart · Rows 30" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | — |
| March | Transplant Outdoors Direct Sow |
| April | — |
| May | Harvest |
| June | Harvest |
| July | Harvest |
| 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 8b
Growing Season
279 days
Growing Tips for Grimes 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 Grimes County, TX?
Grimes County is in Zone 8b with an average last frost of February 25. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Grimes County, TX?
Grimes County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is February 25 and first fall frost is December 1.
Plan Your Garden with Confidence
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