When to Plant Watermelon in Runnels County, TX
Watermelon is a sprawling vine crop that produces sweet, juicy fruits in hot weather. Varieties range from personal-sized icebox types to 50-pound giants.
Runnels County, Texas is in USDA Zone 7b. The average last spring frost is March 19 and the first fall frost is November 15, giving you a growing season of approximately 241 days.
At an elevation of 4,833 feet, Runnels County receives approximately 47.6 inches of rainfall annually with predominantly loam soil. Summer highs average 90°F, providing good warmth for Watermelon during the growing season.
Runnels County Soil Profile
Soil Type
Loam
Soil pH
6.3-7.1
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 Runnels County
How your county's soil matches Watermelon's growing requirements.
Soil pH
Your soil pH (6.3–7.1) is within Watermelon's preferred range (6.0–7.5).
Soil Texture
The loam soil in Runnels County is excellent for Watermelon — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is low (2.0%). Add 2-3 inches of compost before planting Watermelon.
How to Plant Watermelon
Succession Planting Watermelon
Sow every 8 weeks. Last sowing by Aug 07 to harvest before frost.
Plant Water Budget
Monthly Watering Guide for Watermelon
Watermelon needs approximately 1.5 inches of water per week (6.5" per month). Here's how your county's rainfall compares month by month.
| Month | Watermelon Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1" | 0" | ❄️ Dormant |
| Feb | — | 1.6" | 0" | ❄️ Dormant |
| Mar | 6.5" | 3" | 3.5" | 🚿 Regular watering |
| Apr | 6.5" | 4.9" | 1.6" | 💧 Light watering |
| May | 6.5" | 7.4" | 0" | ✅ Rainfall sufficient |
| Jun | 6.5" | 8.1" | 0" | ✅ Rainfall sufficient |
| Jul | 6.5" | 6.3" | 0.2" | 💧 Light watering |
| Aug | 6.5" | 5.1" | 1.4" | 💧 Light watering |
| Sep | 6.5" | 4.2" | 2.3" | 💧 Light watering |
| Oct | 6.5" | 3.2" | 3.3" | 🚿 Regular watering |
| Nov | 6.5" | 1.5" | 5" | 🚿 Regular watering |
| Dec | — | 1.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Mar–Nov in Runnels County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Watermelon 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.
Watermelon Planting Timeline — Runnels County, TX
Watermelon Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 19 | Feb 19 – Mar 5 |
| Transplant Outdoors | April 2 | Apr 2 – Apr 16 |
| Direct Sow | March 26 | Mar 26 – Apr 16 |
| Harvest | June 11 | Jun 11 – Jul 30 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors Direct Sow |
| May | — |
| June | Harvest |
| July | Harvest |
| August | — |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
1.5"/week · 1-2 times/week
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: ideal
🗺️ USDA Zone
Zone 7b
📆 Growing Season
241 days in Runnels County
Growing Tips for Watermelon in Runnels County
Direct sow Watermelon outdoors after March 19 in Runnels County when soil has warmed and frost danger has passed.
Common pests for Watermelon in this region include squash vine borer and cucumber beetles. Use row covers early in the season and inspect plants weekly.
General growing tips
Start seeds indoors 3-4 weeks early or direct sow after soil is warm. Plant on mounds with plenty of space. Check ripeness by looking for a yellow ground spot and dull thump when tapped.
Recommended Watermelon Varieties for Runnels County
Full-size melons that thrive with your long season
Companion Planting
Good Companions
Avoid Planting Near
Check more plant combinations with our Companion Planting Checker →
Watermelon in Other Locations
Frequently Asked Questions
When should I plant Watermelon in Runnels County, TX?
Runnels County is in Zone 7b with an average last frost of March 19. Plan your Watermelon planting based on this frost date — see the calendar above for exact timing.
What planting zone is Runnels County, TX?
Runnels County, Texas is in USDA Hardiness Zone 7b. The average last spring frost is March 19 and first fall frost is November 15.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Runnels County gardeners in Zone 7b organize planting dates, track what's growing, and never miss a planting window.
Get Your Free Garden Planner →Free download. Plan your entire garden season in minutes.