When to Plant Watermelon in Frio 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.
Frio County, Texas is in USDA Zone 9a. The average last spring frost is February 26 and the first fall frost is November 26, giving you a growing season of approximately 273 days.
At an elevation of 3,892 feet, Frio County receives approximately 51 inches of rainfall annually with predominantly loam soil. Summer highs average 93°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.
Frio County Soil Profile
Soil Type
Loam
Soil pH
6.4-7.2
Drainage
Well Drained
How Much Watermelon to Grow
For a family of 4, plant approximately 4 watermelon plants in about 8 sq ft. In Frio County's 273-day season, you'll have plenty of time for a full harvest. Plan your garden layout →
Monthly Watering Guide for Watermelon
Watermelon needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.
| Month | Watermelon Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.2" | 0" | ❄️ Dormant |
| Feb | 4.3" | 1.9" | 2.4" | 🚿 Regular watering |
| Mar | 4.3" | 3.6" | 0.7" | 💧 Light watering |
| Apr | 4.3" | 4.9" | 0" | ✅ Rainfall sufficient |
| May | 4.3" | 7.5" | 0" | ✅ Rainfall sufficient |
| Jun | 4.3" | 9.4" | 0" | ✅ Rainfall sufficient |
| Jul | 4.3" | 6.3" | 0" | ✅ Rainfall sufficient |
| Aug | 4.3" | 5.2" | 0" | ✅ Rainfall sufficient |
| Sep | 4.3" | 4.6" | 0" | ✅ Rainfall sufficient |
| Oct | 4.3" | 3.4" | 0.9" | 💧 Light watering |
| Nov | 4.3" | 1.6" | 2.7" | 🚿 Regular watering |
| Dec | — | 1.4" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Feb–Nov in Frio County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Watermelon Planting Timeline — Frio County, TX
Watermelon Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | January 29 | Jan 29 – Feb 12 |
| Transplant Outdoors | March 5 | Mar 5 – Mar 19 |
| Direct Sow | February 26 | Feb 26 – Mar 19 |
| Harvest | May 14 | May 14 – Jul 2 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | Start Indoors |
| February | Start Indoors Direct Sow |
| 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
Moderate — regular watering
📅 Days to Maturity
70–100 days
🧪 Soil pH
Needs 6–7.5 · Your soil: N/A
🗺️ USDA Zone
Zone 9a
📆 Growing Season
273 days in Frio County
Growing Tips for Frio County
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.
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 Frio County, TX?
Frio County is in Zone 9a with an average last frost of February 26. Plan your Watermelon planting based on this frost date — see the calendar above for exact timing.
What planting zone is Frio County, TX?
Frio County, Texas is in USDA Hardiness Zone 9a. The average last spring frost is February 26 and first fall frost is November 26.
Your Frio County Garden Planner — Free
A 22-page printable planner built for Frio 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.