When to Plant Sunflower in Delta County, TX
Your July game plan for Delta County, Texas
July is a pivotal month for Delta County, Texas gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Pick sunflower
The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.
To set up a strong August, finish these tasks
- First harvests: sunflower
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.
Delta County, Texas is in USDA Zone 8b. The average last spring frost is March 15 and the first fall frost is November 15, giving you a growing season of approximately 245 days.
At an elevation of 235 feet, Delta County receives approximately 70.9 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.
Delta County Soil Profile
Soil Type
Sandy Loam
Soil pH
5.4-6.8
Drainage
Well Drained
Sunflower 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.
Soil Compatibility in Delta County
How your county's soil matches Sunflower's growing requirements.
Soil pH
Your soil pH (5.4–6.8) overlaps with Sunflower's range (6.0–7.5), though not a perfect match.
Soil Texture
Sandy soil in Delta County warms quickly in spring but drains fast. Sunflower will need more frequent watering and regular compost additions to retain nutrients.
Drainage
Drainage is adequate for Sunflower.
Organic Matter
Organic matter is moderate (2.2%). Annual compost additions will help Sunflower.
How to Plant Sunflower
Succession Planting Sunflower
Sow every 8 weeks. Last sowing by Aug 07 to harvest before frost.
Sunflower Water Budget
Monthly Watering Guide for Sunflower
Sunflower needs approximately 0.5 inches of water per week (2.2" 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 | — | 2.7" | 0" | ❄️ Dormant |
| Mar | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 6.8" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 10.6" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 11.2" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 8.2" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 9.9" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 6.7" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 4.6" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 2.3" | 0" | ✅ Rainfall sufficient |
| Dec | — | 2" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Delta County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Sunflower Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Sunflower Planting Timeline — Delta County, TX
Sunflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 22 | Feb 22 – Mar 8 |
| Transplant Outdoors | March 1 | Mar 1 – Mar 15 |
| Direct Sow | March 1 | Mar 1 – Mar 22 |
| Bloom | May 24 | May 24 – Oct 11 |
Plant 1" deep · 18" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Transplant Outdoors 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
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 8b
📆 Growing Season
245 days in Delta County
Growing Tips for Sunflower in Delta County
Direct sow Sunflower outdoors after March 15 in Delta County when soil has warmed and frost danger has passed.
Sandy soil in Delta County dries quickly — mulch Sunflower with 2-3 inches of straw and water deeply 2-3 times per week rather than lightly every day.
Common pests for Sunflower in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
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 Delta County, TX?
Delta County is in Zone 8b with an average last frost of March 15. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Delta County, TX?
Delta County, Texas is in USDA Hardiness Zone 8b. The average last spring frost is March 15 and first fall frost is November 15.
Your Delta County Garden Planner — Free
A 22-page printable planner built for Delta County (Zone 8b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.