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Watermelon

Citrullus lanatus

Fruit

Watermelons are sprawling warm-season vines that require a long, hot growing season to produce their large, sweet fruits. They thrive in sandy, well-draining soil and need consistent pollinator activity for good fruit set.

Growing Conditions

Sunlight

Full Sun

Water Needs

Moderate

Soil

Sandy, well-draining loam; pH 6.0–6.8

Spacing

36–60 inches

Days to Maturity

70–90 days from transplant

Growing Zones

1
2
3
4
5
6
7
8
9
10
11
12
13

Thrives in USDA Zones 6–11

Companion Planting

Good Companions

Keep Away From

When to Plant

  • Start Indoors

    3–4 weeks before last frost

  • Transplant

    2 weeks after last frost, soil 70°F+

  • Harvest

    Check tendril near fruit is dry; thump fruit for a hollow sound

Organic Growing Tips

  • Plant on black plastic mulch to maximise soil warmth and accelerate fruiting in short seasons.

  • Hand-pollinate early morning flowers if bees are scarce using a small paintbrush.

  • Plant borage and marigolds throughout the patch to attract pollinators and repel cucumber beetles.

  • Water deeply but infrequently; reduce watering 2 weeks before harvest to concentrate sugars.

Common Pests

  • Cucumber Beetle
  • Aphids
  • Squash Bug
  • Fusarium Wilt
  • Alternaria Blight

All pest management in Garden uses safe, organic, non-toxic methods only. No synthetic pesticides, ever.