NOVELTY - Interplanting watermelon and sugarcane comprises e.g. selecting fertile land, selecting sugar cane and watermelon variety with high yield, deep turning soil, fertilizing, applying bio-fertilizer, film covering, seedling culture of sugarcane and watermelon, transplanting sugar cane seedling and watermelon seedling after a month, planting sugarcane in the side line and watermelon in the middle line, reinforcing water management, controlling pest, applying bio-fertilizer after water melon fruit is grown, promoting fruit enlargement, harvesting watermelon, lifting film, and cultivating sugarcane.    USE - The method is useful for interplanting watermelon and sugarcane (claimed).    ADVANTAGE - The method is economical, is easy to manage, can achieve high harvesting of cane and melon at the same time, produces sugarcane with high sugar content and large and sweet watermelon, can make full use of land and illumination condition, improves the single time planting during soil degradation phenomenon, and increases the income of the farmer.    DETAILED DESCRIPTION - Interplanting watermelon and sugarcane, comprises (i) selecting fertile land with deep soil layer, easy for irrigation and draining, (ii) selecting sugar cane and watermelon variety with high yield and quality, (iii) deep turning soil, fertilizing, applying basal fertilizer, then applying bio-fertilizer of 700-800 kg/acre, and film covering whole stretch, (iv) using sugarcane double-film covering seedling culture, and watermelon nutrition pot covered seedling culture, transplanting sugar cane seedling and watermelon seedling after a month, planting the sugarcane in the side line and watermelon in the middle line, and (v) reinforcing fertilizer and water management and controlling pest, applying additional biological fertilizer of 800-1000 kg/acre after water melon fruit is grown, promoting fruit enlargement, and paying attention to clear the drainage ditch, grass covering, pruning and controlling insect, watermelon harvesting after pulling vine, lifting the film in time for cultivating sugarcane and applying sufficient fertilizer.