The demand for N, P, and K nutrients per cucumber per tonne of commercial vegetables is 2.73:1.3:3.47 (kg), which can also be converted into 2.1:1:2.669. However, for a long time, some vegetable farmers do not understand or ignore this basic requirement of fertilizer laws. They are blindly used and randomly used. As a result, the proportion of N, P, and K nutrients in the soil is imbalanced, and the accompanying micronutrient deficiencies and various The increase in difficult diseases has caused some undue economic losses. Recently, some farmers have found the author to reflect the sudden illness of the greenhouse cucumber planted outside China. They are very tricky and they come here specifically for help. The vegetable farmer applied urea (46% nitrogen) 50 kilograms and diammonium phosphate (18:46:0) 50 kilograms at the end of an acre of cucumber greenhouse, which has entered the results period. Six or seven days ago, Mu applied 40 kg of urea. There is now a gradual leaf-membrane spread at the tip of the leaf tip. The lower leaves are partially scorched, curled, wilted, and have brown spots. The leaves gradually develop upward. The melon section is thick and short and the fruit development is blocked. Photos. According to the situation, the author immediately told him that this is a disproportionate ratio of NPK, a serious lack of potassium, nitrogen overdose, and even caused the typical symptoms of calcium deficiency. Because vegetables are the crops that require large amounts of potassium, especially cucumbers, because of their high fruit yields, the absorption of potassium is higher than that of nitrogen. The ratio of nitrogen, phosphorus and potassium in the vegetable shed's greenhouse is 100.8:46: 0. The shortage of potassium fertilizer and excessive nitrogen content increase the soil solution concentration, reduce and inhibit the absorption of calcium, and cause calcium deficiency. Therefore, it is recommended to use high-potassium-rich 55% Eurasian brand multi-functional water-soluble fertilizer, 6 kg per mu, and spraying 2-3 times with expanding fruit potassium Bao, Talon calcium, calorific boron, and rare earth. Vegetable farmers are more recognized. Shenzhen Sunson Tech Co., Ltd , https://www.sunsonkiosk.com