JuiceBox Organic (F1) Watermelon Seed

Scientific name

Citrullus lanatus var. lanatus

Soil and warmth

Watermelons do best in light, free-draining soil at pH 6.5–7.5 on a sunny, south-facing site. Keep the soil evenly moist while plants establish and while fruit is setting, then hold back water in the final week before ripening, since heavy watering then can dilute flavor. The crop needs steady heat, so plastic mulch and row cover pay off with earlier, larger harvests, particularly in northern areas. Take covers off once female flowers (with a tiny fruit behind the bloom) appear so insects can pollinate.

Days to maturity

Counted from transplanting. Direct-sown plants need roughly 10 more days.

Transplanting

Start plants about a month before setting out (no earlier), in 50-cell trays or 2–3" pots. Sow 2 seeds per cell, 1/2–1" deep, and keep at 80–90°F (27–32°C) until they emerge, then grow on at about 75°F (24°C). Never let the mix dry out. Harden off for a week with a little less water and warmth. Plant out only once the weather is settled and frost-free: 2–3' apart in rows 6–8' apart, or snip to one seedling per cell and plant 18" apart. Even hardened plants are delicate, so keep the root ball intact and water well.

Direct sowing

Wait 1–2 weeks past the last frost, until the soil is above 70°F (21°C). Sow 3 seeds per spot every 18–36", 1/2–1" deep, and thin to the strongest plant.

Seeding rate

At 3 seeds every 18" in rows 6' apart: about 1,000 seeds per 500 ft.

Seedless (triploid) types

Start these indoors in good conditions, as they are fussier to germinate. They need a regular seeded watermelon planted nearby as a pollenizer to set fruit. The fruit is nearly seedless, though a few seeds can form under stress.

Insect pests

Cover plants with row cover at planting to keep cucumber beetles off, or use an approved insecticide such as pyrethrin or azadirachtin.

Disease

Pick varieties with resistance to the diseases common where you farm. Late in summer, vines carrying a heavy load of fruit can collapse almost overnight ("sudden wilt"), often after cold stress; good feeding and steady watering help prevent it.

Ripeness

Look for three signs: the curly tendril closest to the fruit stem has browned and dried; the patch where the melon sits on the soil has turned from pale greenish white to cream or yellow; and a flick of the finger gives a dull, hollow sound rather than a sharp, high one.

Storage

Watermelons keep 2–3 weeks at 45–50°F (7–10°C) and 85–95% relative humidity.

Packet

15 seeds.

Seeds per lb.

About 6,800 on average.