Field guide
How to grow watermelon: planting, care, and harvest guide
Watermelon typically reaches first harvest in 70–90 days. This guide covers when to plant by USDA zone, common pests, harvest cues, and companion plants where relevant.
Open plannerWhen to plant watermelon by USDA zone group
- USDA Zones 1–4 — June
- USDA Zones 5–6 — May to June
- USDA Zones 7–8 — April to May
- USDA Zones 9–10 — March to April
- USDA Zones 11–13 — February to March
Companion plants
Good companions: Sweet Corn, Sunflowers, Radishes
Avoid planting with: Potatoes
Harvest
When to pick
- Tendril nearest the fruit turns brown and dries
- Ground spot (where fruit rests) turns from white to creamy yellow
- Thump test: hollow sound means ripe, high-pitched means not ready
How: Cut stem with a sharp knife, leaving 2 inches of vine. Don't pull or twist.
Storage: Whole uncut watermelon keeps at room temp for 1-2 weeks. Refrigerate cut melon, wrapped, for 3-5 days.
Common pests and problems
Cucumber Beetle
Signs: Chewed leaves and flowers, bacterial wilt transmission
Control: Row covers until flowering. Hand-pick. Kaolin clay.
Aphids
Signs: Curled leaves, sticky residue
Control: Water spray, insecticidal soap.
About this field guide
A local-first garden agent and neighborhood commons planner for food, water, tools, repair, clean energy, and resilient communication. Your profile and garden history stay on this device.