The use of nitrogenous fertilizer in vegetable gardens is one of the effective measures to increase the yield of vegetables, but if used improperly, it will cause pollution to vegetables and reduce the quality of vegetables. To reduce the pollution of nitrogen fertilizers on vegetables, we must pay attention to the following four points: Deep application of nitrogen fertilizer can significantly reduce its direct contact with the air and sunlight, so as to avoid volatile loss and pollution of vegetables. Generally, nitrogen fertilizer should be applied in a depth of 10-15 cm. For planting roots with developed root vegetables, dioscorea and root vegetables, nitrogen fertilizer should be applied deep to the root layer below 15 cm. Early application of leafy vegetables and vegetables with short growth period should be applied as soon as possible. Generally, it is better to apply nitrogen fertilizer at seedling stage, and nitrogen fertilizer should not be used excessively in the late growth stage of vegetables. For vegetables that do not absorb nitrate easily, nitrogen fertilizer should be stopped 30 days before harvest. The cumulative amount of nitrate in vegetables with controlled consumption will increase with the increase in the amount of nitrogen fertilizer application. Therefore, the amount of nitrogen fertilizer applied and the number of applications should be reduced as much as possible. Generally, the amount of nitrogen fertilizer per acre should be controlled below 20 kg nitrogen, and the vegetable fields with higher fertility should be controlled under 10 kg or no nitrogen fertilizer. If nitrogen fertilizer is required, 70-80% of nitrogen fertilizer should be used as a base fertilizer, and the rest should be used for deep seedling application. Avoid foliar spray leafy vegetables should not be sprayed on the surface of nitrogen fertilizer. Because ammonium ions in nitrogen fertilizers are easily converted into nitrate ions when they come in contact with air, they are absorbed by leaves, and the short growing period of leafy vegetables makes it easy for nitrates to accumulate in leaves. Therefore, do not apply foliar nitrogenous fertilizers to leafy vegetables. In particular, foliar sprays must not be conducted within 28 days before harvest to prevent contamination of vegetables. Seasoned Peanuts,Boiled Peanut Salad,Boiled Groundnut Salad,Raw Peanut Salad DALIAN HAIBAO FOODS CO., LTD. , https://www.haibaoseafoods.com