When to Plant Sunflower in Waller County, TX
May to-do list for Waller County, Texas
We've pulled the most time-sensitive tasks for Waller County, Texas this May and put them front and centre. Tackle them in order.
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Harvest sunflower as they ripen
Taste as you pick. The first ripe produce is the best feedback loop you'll get all season.
June will be here before you know it — start on
- First harvests: sunflower
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.
Waller County, Texas is in USDA Zone 9a. The average last spring frost is February 19 and the first fall frost is December 4, giving you a growing season of approximately 288 days.
At an elevation of 376 feet, Waller County receives approximately 64.1 inches of rainfall annually with predominantly sandy loam soil. Summer highs average 95°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.
Waller County Soil Profile
Soil Type
Sandy Loam
Soil pH
5.6-6.2
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.
Soil Compatibility in Waller County
How your county's soil matches Sunflower's growing requirements.
Soil pH
Your soil pH (5.6–6.2) is more acidic than Sunflower prefers (6.0–7.5). Add garden lime to raise pH.
Soil Texture
Sandy soil in Waller County warms quickly in spring but drains fast. Sunflower will need more frequent watering and regular compost additions to retain nutrients.
Organic Matter
Organic matter is moderate (2.0%). Annual compost additions will help Sunflower.
How to Plant Sunflower
Succession Planting Sunflower
Sow every 8 weeks. Last sowing by Aug 26 to harvest before frost.
Plant 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 | — | 1.7" | 0" | ❄️ Dormant |
| Feb | 2.2" | 2.4" | 0" | ✅ Rainfall sufficient |
| Mar | 2.2" | 4.6" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 7.3" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 8.9" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 9.1" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 7.9" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 7" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 6.9" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 4.3" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 2.2" | 0" | ✅ Rainfall sufficient |
| Dec | 2.2" | 1.7" | 0.5" | 💧 Light watering |
Water needs are for active growing months only (Feb–Dec in Waller 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 — Waller County, TX
Sunflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 8 | Jan 8 – Jan 22 |
| Transplant Outdoors | February 26 | Feb 26 – Mar 12 |
| Direct Sow | February 19 | Feb 19 – Mar 12 |
| Harvest | May 7 | May 7 – Jun 25 |
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 | — |
| May | Harvest |
| June | Harvest |
| July | — |
| August | — |
| September | — |
| October | — |
| 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: too_acidic
🗺️ USDA Zone
Zone 9a
📆 Growing Season
288 days in Waller County
Growing Tips for Sunflower in Waller County
Direct sow Sunflower outdoors after February 19 in Waller County when soil has warmed and frost danger has passed.
Sandy soil in Waller 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 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
Check more plant combinations with our Companion Planting Checker →
Sunflower in Other Locations
Frequently Asked Questions
When should I plant Sunflower in Waller County, TX?
Waller County is in Zone 9a with an average last frost of February 19. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Waller County, TX?
Waller County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 19 and first fall frost is December 4.
Your Waller County Garden Planner — Free
A 24-page printable planner built for Waller 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.