When to Plant Watermelon in Decatur 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.
Decatur County, Indiana is in USDA Zone 6a. The average last spring frost is April 10 and the first fall frost is October 20, giving you a growing season of approximately 193 days.
At an elevation of 985 feet, Decatur County receives approximately 32.5 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Watermelon during the growing season.
Decatur County Soil Profile
Soil Type
Silt Loam
Soil pH
6.2-7.1
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 — Decatur County, IN
Watermelon Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | March 6 | Mar 6 – Mar 20 |
| Transplant Outdoors | April 24 | Apr 24 – May 8 |
| Direct Sow | April 17 | Apr 17 – May 8 |
| Harvest | July 3 | Jul 3 – Aug 21 |
Plant 1" deep · 30" apart · Rows 42" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | Start Indoors |
| April | Transplant Outdoors 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 6a
Growing Season
193 days
Growing Tips for Decatur 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 Decatur County, IN?
Decatur County is in Zone 6a with an average last frost of April 10. Plan your Watermelon planting based on this frost date — see the calendar above for exact timing.
What planting zone is Decatur County, IN?
Decatur County, Indiana is in USDA Hardiness Zone 6a. The average last spring frost is April 10 and first fall frost is October 20.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Decatur County gardeners in Zone 6a organize planting dates, track what's growing, and never miss a planting window.
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