When to Plant Watermelon in DeWitt 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.
DeWitt County, Texas is in USDA Zone 8b. 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 Watermelon during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Watermelon root diseases.
DeWitt County Soil Profile
Soil Type
Loam
Soil pH
6.8-7.8
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 DeWitt County
How your county's soil matches Watermelon's growing requirements.
Soil pH
Your soil pH (6.8–7.8) overlaps with Watermelon's range (6.0–7.5), though not a perfect match.
Soil Texture
The loam soil in DeWitt County is excellent for Watermelon — good drainage, moisture retention, and nutrient holding capacity.
Drainage
Drainage is adequate for Watermelon.
Organic Matter
Organic matter is low (1.9%). Add 2-3 inches of compost before planting Watermelon.
How to Plant Watermelon
Succession Planting Watermelon
Sow every 8 weeks. Last sowing by Aug 18 to harvest before frost.
Plant Water Budget
Water stress score is 6/10 — consider drought-tolerant varieties and mulching
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 | — | 1.8" | 0" | ❄️ Dormant |
| Feb | — | 2.1" | 0" | ❄️ Dormant |
| Mar | 6.5" | 4" | 2.5" | 💧 Light watering |
| Apr | 6.5" | 5.9" | 0.6" | 💧 Light watering |
| May | 6.5" | 9.1" | 0" | ✅ Rainfall sufficient |
| Jun | 6.5" | 11.3" | 0" | ✅ Rainfall sufficient |
| Jul | 6.5" | 6.9" | 0" | ✅ Rainfall sufficient |
| Aug | 6.5" | 7.9" | 0" | ✅ Rainfall sufficient |
| Sep | 6.5" | 5.6" | 0.9" | 💧 Light watering |
| Oct | 6.5" | 3.7" | 2.8" | 💧 Light watering |
| Nov | 6.5" | 2.3" | 4.2" | 🚿 Regular 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.
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 — DeWitt County, TX
Watermelon Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 2 | Feb 2 – Feb 16 |
| Transplant Outdoors | March 16 | Mar 16 – Mar 30 |
| Direct Sow | March 9 | Mar 9 – Mar 30 |
| Harvest | May 25 | May 25 – Jul 13 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| 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
1.5"/week · 2-3 times/week
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: acceptable
🗺️ USDA Zone
Zone 8b
📆 Growing Season
269 days in DeWitt County
Growing Tips for Watermelon in DeWitt County
Direct sow Watermelon outdoors after March 02 in DeWitt 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 DeWitt 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 DeWitt County, TX?
DeWitt County is in Zone 8b with an average last frost of March 2. Plan your Watermelon 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 8b. The average last spring frost is March 2 and first fall frost is November 26.
Plan Your Garden with Confidence
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