When to Plant Watermelon in Warren County, IN
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.
Warren County, Indiana is in USDA Zone 5b. The average last spring frost is April 19 and the first fall frost is October 14, giving you a growing season of approximately 178 days.
At an elevation of 764 feet, Warren County receives approximately 40.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86°F, providing good warmth for Watermelon during the growing season.
Warren County Soil Profile
Soil Type
Silt Loam
Soil pH
5.9-7.1
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.
Plant Water Budget
Watermelon Planting Timeline — Warren County, IN
Watermelon Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 15 | Mar 15 – Mar 29 |
| Transplant Outdoors | May 3 | May 3 – May 17 |
| Direct Sow | April 26 | Apr 26 – May 17 |
| Harvest | July 12 | Jul 12 – Aug 30 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Direct Sow |
| May | Transplant Outdoors Direct Sow |
| June | — |
| July | Harvest |
| August | Harvest |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
Sun
Full Sun (6-8+ hours)
Water
Moderate — regular watering
Days to Maturity
70–100 days
Soil pH
6 – 7.5
USDA Zone
Zone 5b
Growing Season
178 days
Growing Tips for Warren 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
Level Up Your Garden
Watermelon in Other Locations
Frequently Asked Questions
When should I plant Watermelon in Warren County, IN?
Warren County is in Zone 5b with an average last frost of April 19. Plan your Watermelon planting based on this frost date — see the calendar above for exact timing.
What planting zone is Warren County, IN?
Warren County, Indiana is in USDA Hardiness Zone 5b. The average last spring frost is April 19 and first fall frost is October 14.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Warren County gardeners in Zone 5b organize planting dates, track what's growing, and never miss a planting window.
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