When to Plant Sunflower in Medina County, TX
May in the garden — Medina County, Texas
If you only do a handful of things in the garden this May, make it these. They're sequenced around your zone's frost timing.
-
Bring in the sunflower
The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.
June prep starts now
- 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.
Medina County, Texas is in USDA Zone 9a. The average last spring frost is March 3 and the first fall frost is November 23, giving you a growing season of approximately 265 days.
At an elevation of 1,498 feet, Medina County receives approximately 56.7 inches of rainfall annually with predominantly loam soil. Summer highs average 92°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.
Medina County Soil Profile
Soil Type
Loam
Soil pH
6.6-7.6
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 Medina County
How your county's soil matches Sunflower's growing requirements.
Soil pH
Your soil pH (6.6–7.6) overlaps with Sunflower's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in Medina County is excellent for Sunflower — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is low (1.9%). Add 2-3 inches of compost before planting Sunflower.
How to Plant Sunflower
Succession Planting Sunflower
Sow every 8 weeks. Last sowing by Aug 15 to harvest before frost.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 1.5" | 0" | ❄️ Dormant |
| Feb | — | 1.9" | 0" | ❄️ Dormant |
| Mar | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| Apr | 2.2" | 5.6" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 8.1" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 8" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 8.3" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 6.8" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 5.6" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 4.1" | 0" | ✅ Rainfall sufficient |
| Nov | 2.2" | 1.9" | 0.3" | 💧 Light watering |
| Dec | — | 1.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Medina 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 — Medina County, TX
Sunflower Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 20 | Jan 20 – Feb 3 |
| Transplant Outdoors | March 10 | Mar 10 – Mar 24 |
| Direct Sow | March 3 | Mar 3 – Mar 24 |
| Harvest | May 19 | May 19 – Jul 7 |
Plant 1" deep · 18" apart · Rows 30" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors |
| 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
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 9a
📆 Growing Season
265 days in Medina County
Growing Tips for Sunflower in Medina County
Direct sow Sunflower outdoors after March 03 in Medina County when soil has warmed and frost danger has passed.
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 Medina County, TX?
Medina County is in Zone 9a with an average last frost of March 3. Plan your Sunflower planting based on this frost date — see the calendar above for exact timing.
What planting zone is Medina County, TX?
Medina County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is March 3 and first fall frost is November 23.
Your Medina County Garden Planner — Free
A 24-page printable planner built for Medina 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.