The fertilization period for grapes should be based on the growth and development needs of the grapes. According to the different stages of the grape growth cycle, the specific periods of fertilization in a year are:

(1) Base fertilizer is the most important fertilization in a year. This fertilization has an impact on the growth of grapes throughout the year. important impact. The fertilizing period is usually done in late autumn, before the grape plants enter dormancy. Mainly organic fertilizers are used, combined with phosphorus and calcium fertilizers. After the organic fertilizer is decomposed in the soil in winter, it will be used for the growth of the plant in the second year, and it will also play a role in the regeneration of roots that were cut off that year. When the protected area is densely planted, furrow application is often used. The amount of fertilizer applied is 3000 to 4000 kilograms of organic fertilizer per 666.7 square meters, combined with 1.5 to 2.0 kilograms of phosphorus and calcium fertilizer.

(2) Top dressing according to needs during the growing season. In the Beijing area, top dressing is generally done 3 to 4 times a year, mainly with quick-acting fertilizers.

The first time is carried out before germination, mainly using nitrogen fertilizer. Decomposed human feces, urea, ammonium bicarbonate, ammonium sulfate, etc. can be applied. Apply 15 to 20 kilograms of urea or compound fertilizer per 666.7 square meters.

The second top dressing can be done after fruit setting. When the berries grow to the size of soybeans, about 15 kilograms of human excrement or nitrogen, phosphorus, potassium compound fertilizer or urea can be applied.

The third fertilization is done when the fruits begin to color. This time the top dressing should be mainly potassium fertilizer, combined with an appropriate amount of phosphate fertilizer to improve the quality of the fruit. Apply about 15 kilograms of potassium sulfate per 666.7 square meters, or spray 0.2% potassium dihydrogen phosphate.

The fourth top dressing is carried out after harvest, mainly using phosphorus and potassium fertilizers. The purpose is to restore the tree vigor, promote the maturity of branches and store nutrients.