NOVELTY - Environment-friendly cultivation of organic watermelon involves culturing and germinating watermelon seedlings as scion; taking white pumpkin seeds as rootstock, grafting, and carrying out grafting management to ensure good healing; mixing 1000 kg manure, 1000 kg crushed straw, and 40 kg calcium cyanamide, scattering in greenhouse, watering until moisture content of 30-40%, covering with film, and sealing for 15 days to prepare fertilizer; and opening film, adding 20-30 kg potash, 45-55 kg superphosphate, and 100-130 g fine soil, mixing, and spreading in greenhouse.    USE - Method for environment-friendly cultivating organic watermelon (claimed).    ADVANTAGE - The method uses less inorganic fertilizer and low-toxicity drugs, avoids risk of thin-skinned watermelons burst, is simple, and reduces investment cost.    DETAILED DESCRIPTION - Environment-friendly cultivation of organic watermelon comprises:    (A) culturing and germinating watermelon seedlings as scion;    (B) taking white pumpkin seeds as rootstock, grafting, and carrying out grafting management to ensure good healing;    (C) mixing 1000 kg manure, 1000 kg crushed straw, and 40 kg calcium cyanamide, scattering in greenhouse, watering until moisture content of 30-40%, covering with film, and sealing for 15 days to prepare fertilizer;    (D) opening film, adding 20-30 kg potash, 45-55 kg superphosphate, and 100-130 g fine soil, mixing, spreading in greenhouse, rotary tilling, and ridging;    (E) transplanting grafted seedlings;    (F) root irrigating with fungicides, insecticides, and plant growth regulator;    (G) topping with 45-60 g fertilizer when grafted seedlings grow 5 main vine leaf;    (H) carrying out artificial pollination of flowers;    (I) selecting best watermelon per plant, removing other watermelon, and top dressing;    (J) dressing for 2 times at intervals of 9-12 days, where dressing comprises 10 kg water-soluble potassium fertilizer, 2 kg effective microorganisms bacterial solution, 2 kg potassium humate compost, prepared by dissolving raw materials in water;    (K) spraying pesticides for 2-3 times to control disease at interval of 7 days, where pesticide is bromochloroisocyanuric acid and bismerthiazol; and    (L) spraying sweetener for 2-3 times at interval of 5 days and harvesting.