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Watermelon

Citrullus lanatus · Cucurbitaceae

Description​

Watermelon is a large, juicy fruit characterized by its green rind and sweet, watery, red or pink flesh. It is particularly known for its refreshing taste and high water content, typically around 90%.

Where it Grows​

Planting​

When to Plant​

  • Spring: Ideal planting time is after the danger of frost has passed and soil temperatures are consistently above 70°F (21°C).

How to Plant​

  1. Choose a sunny location with well-drained soil.
  2. Prepare the soil by tilling and adding organic matter.
  3. Plant seeds 1 inch deep and 36-42 inches apart in rows.
  4. Water deeply after planting.

Planting Calendar​

  • Start seeds indoors: 3–4 weeks before the last frost
  • Sow outdoors: 2–3 weeks after the last frost
  • Plant outdoors: 2–3 weeks after the last frost
  • Germination: 4–10 days
Plant
JanFebMarAprMayJunJulAugSepOctNovDec
Watermelon
Start indoors: Mar 13 – Mar 26Sow outdoors: Apr 24 – May 7Plant out: Apr 24 – May 7Harvest: Jul 3 – Sep 5
Start indoors Sow outdoors Plant out HarvestBased on zone 6: last frost around Apr 10, first frost around Oct 25.
  • Start indoors: Mar 13 – Mar 26
  • Sow outdoors: Apr 24 – May 7
  • Plant out: Apr 24 – May 7
  • Harvest: Jul 3 – Sep 5

Care​

Watering​

  • Water regularly, especially during dry spells; aim for about 1-1.5 inches of water per week.

Weeding​

  • Regularly check for weeds and remove them as they compete for nutrients and water.

Mulching​

  • Apply organic mulch around plants to conserve moisture and suppress weeds.

Fertilizing​

  • Use a balanced fertilizer when seedlings are established and again when they start to produce fruit.

Thinning​

  • Thin seedlings to one per hill when they reach about 4 inches tall to ensure adequate space for growth.

Pest Management​

  • Monitor for pests such as aphids and beetles; consider using organic insecticidal soap or neem oil.

Harvesting​

  • Harvest when the tendril nearest the fruit turns brown and the fruit shows a dull sheen.

Growing in Containers​

Grows well in a pot of at least 40 litres (11 US gallons), with drainage holes. Best kept outdoors.

Propagation​

From seed​

  1. Start seeds indoors in individual pots 3–4 weeks before the last frost, or sow outdoors once the soil reaches about 21°C (70°F).
  2. Sow seeds 2–3 cm (about 1 inch) deep.
  3. Keep the soil warm and evenly moist until seeds sprout.
  4. Harden off indoor-grown seedlings and plant them out after the last frost, taking care not to disturb their roots.
  5. Thin outdoor-sown seedlings to one or two plants per hill.

Companion Plants​

Good neighbors

  • Borage: Its flowers attract bees that help pollinate watermelon blossoms.
  • Nasturtiums: Their flowers attract pollinators when planted near watermelon vines.

Common Problems​

  • Blossom end rot
  • Powdery mildew
  • Fruit fly infestation
  • Root rot

Pests and diseases: Aphids, Cucumber Beetles, Powdery Mildew, Fusarium Wilt, Anthracnose

Nutrition​

Nutritional Benefits​

  • Low in calories and fat
  • High in hydration
  • Source of vitamins A and C

Nutritional Composition (per 100g)​

NutrientAmount
Calories30 kcal
Water91.45 g
Carbohydrates7.55 g
Protein0.61 g
Fat0.15 g
Fiber0.4 g
Vitamin C8.1 mg
Vitamin A18 mcg

Varieties​

  • Seedless Watermelon
  • Picnic Watermelon
  • Icebox Watermelon
  • Yellow Watermelon
  • Orange Watermelon

Health Benefits​

  • Hydration due to high water content
  • Rich in antioxidants, including lycopene
  • Supports heart health and may help lower blood pressure

Fun Facts​

  • Watermelon is 92% water!
  • The largest watermelon ever recorded weighed 350.5 pounds (158.8 kg).
  • Watermelon seeds can be roasted and eaten as a snack.
  • Watermelon is not a vegetable but a fruit, specifically a berry!