Fertilization characteristics of watermelon covered with plastic film

The yield of watermelon mulched with plastic film is generally about 30% higher than that of open field watermelon, and the amount of fertilizer application should be increased by 20% to 30% accordingly. The plots with a large increase in yield should apply a certain amount of topdressing accordingly. The proportion of base fertilizer and the amount of nitrogen fertilizer in base fertilizer should be properly reduced, and the times and proportion of topdressing should be increased correspondingly. Topdressing can be applied one or two times more than that of watermelon in the open field. In addition to applying organic fertilizer such as cake fertilizer at the initial stage of vine extension, compound fertilizer can also be applied one or two times. Potassium dihydrogen phosphate or urea can also be sprayed as extra-root topdressing. It can also be applied with water, and the membrane can be broken in the later stage of cultivation, and irrigation can be carried out after application in the inter-plant point.