Growing guide

How to Grow Watermelon

The taste of summer — long, hot days turn into sweet, dripping slices.

The basics

What watermelon need

• Sun — Full sun (8+ hours)
• Water — 1–2 inches per week; reduce as fruit ripens for sweetness
• Harvest in 70–100 days from transplant
• Difficulty — Moderate

When to plant

Time it from your frost date

• Start indoors: 3–4 weeks before last frost
• Transplant: 2 weeks after last frost, once soil is 70°F+
• Direct sow: In long-season zones, 2 weeks after last frost
• Best in Zones 4–11 (warm-season annual; easiest in 7+)

How to plant

Three steps to a strong start

• 1. Start indoors in short seasons, or wait for truly warm soil to direct sow.
• 2. Warm the bed with black plastic mulch in cooler zones.
• 3. Transplant carefully — melons resent root disturbance.

Common problem

Vines grow but few fruits set

Needs pollinators and warmth — plant flowers nearby and be patient; early male flowers naturally drop.

Common problem

Bland, mealy fruit

Often too much late water or an immature pick — reduce water as fruit ripens and confirm ripeness before cutting.

Harvest

Picking watermelon right

Check three signs together: the curly tendril nearest the fruit has dried brown, the ground spot has turned creamy yellow, and the rind has dulled. A ripe melon also gives a deep, hollow thunk when tapped.

Gardeners ask

How do I tell when a watermelon is ripe?

The tendril closest to the fruit dries and browns, the underside ground spot turns buttery yellow, and tapping gives a deep hollow sound.

Keep growing

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