Watermelon Seeds,
Charleston Gray

Start seeds indoors 3–4 weeks before the last frost or direct sow once soil temperatures reach at least 70°F. This variety requires a long, warm growing season, making early starts in cooler regions essential. If you’re not sure how to find your first and last frost dates, consult our blog post 'Our Experts Answer Questions, Share Resources.'

Sow 2–3 seeds per mound, 1 inch deep, and space mounds 3–4 feet apart. Thin to the strongest seedling once true leaves emerge. If transplanting starts, handle roots gently and avoid disturbing them. Choose a sunny location with good air circulation and avoid planting near other cucurbits to reduce disease pressure.

Water deeply once or twice per week, depending on rainfall. Fertilize with compost or a balanced organic fertilizer when vines start to run and again at flowering. Keep fruits off bare soil using straw or melon cradles to reduce rot and pest damage. Harvest when the tendril nearest the fruit is dry and the belly spot turns creamy yellow.

• Choose fully ripe or overripe fruits from healthy, true-to-type plants.
• Scoop seeds from the flesh and rinse in a strainer to remove pulp.
• Spread seeds on a screen or paper towel in a warm, dry place out of direct sunlight for 7-10 days.
• Stir daily to ensure even drying.
• Once completely dry, store in an labeled, airtight container in a cool, dark place.