When to Plant Sunflower in DeWitt County, TX
Sunflower (Helianthus annuus) is a fast-growing North American native annual famous for its towering stems and brilliant yellow heads. It thrives in full sun and heat, producing large, pollen-rich blooms that attract bees, butterflies, and seed-eating birds. Varieties range from 18-inch dwarfs to 12-foot giants and nearly every color except blue.
DeWitt County, Texas is in USDA Zone 9a. The average last spring frost is March 2 and the first fall frost is November 26, giving you a growing season of approximately 269 days.
At an elevation of 1,649 feet, DeWitt County receives approximately 62.1 inches of rainfall annually with predominantly loam soil. Summer highs average 91°F, providing good warmth for Sunflower during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Sunflower root diseases.
DeWitt County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.8
Drainage
Well Drained
Monthly Watering Guide for Sunflower
Sunflower needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Sunflower Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.8" | 0" | ❄️ Dormant |
| Feb | — | 2.1" | 0" | ❄️ Dormant |
| Mar | 4.3" | 4" | 0.3" | 💧 Light watering |
| Apr | 4.3" | 5.9" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 9.1" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 11.3" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 6.9" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 7.9" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 5.6" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 3.7" | 0.6" | 💧 Light watering |
| Nov | 4.3" | 2.3" | 2" | 💧 Light watering |
| Dec | — | 1.5" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in DeWitt County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Sunflower Planting Timeline — DeWitt County, TX
Sunflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 9 | Feb 9 – Feb 23 |
| Transplant Outdoors | February 9 | Feb 9 – Feb 23 |
| Direct Sow | February 9 | Feb 9 – Mar 2 |
| Bloom | May 4 | May 4 – Oct 5 |
Plant 1" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors Transplant Outdoors Direct Sow |
| March | Direct Sow |
| April | — |
| May | Bloom |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | Bloom |
| October | Bloom |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
Low — drought tolerant
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: N/A
🗺️ USDA Zone
Zone 9a
📆 Growing Season
269 days in DeWitt County
Growing Tips for DeWitt County
Direct-sow 1 inch deep after last frost; germination takes 7-14 days at 65-75°F soil. Sunflowers dislike root disturbance so direct sowing is strongly preferred over transplanting. Plant in succession every 2 weeks for extended bloom. Stake tall varieties. Avoid overwatering — they tolerate drought once established. Birds will self-deadhead seed heads; leave them up through fall for wildlife.
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Sunflower in Other Locations
Frequently Asked Questions
When should I plant Sunflower in DeWitt County, TX?
DeWitt County is in Zone 9a with an average last frost of March 2. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is DeWitt County, TX?
DeWitt County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is March 2 and first fall frost is November 26.
Your DeWitt County Garden Planner — Free
A 22-page printable planner built for DeWitt County (Zone 9a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.