Fertilization and principles of grapes
The method and frequency of fertilization of grapes
Once before budding, the main fertilizer is nitrogen. It is possible to apply well-rotted human manure and urine, urea, ammonium bicarbonate, ammonium sulfate, etc., with 15-20 kg of urea or compound fertilizer per 666.7 square meters.
The second fertilizer can be done after fruiting. When the berries grow to the size of soybean grain, human manure and urine or nitrogen, phosphorus and potassium compound fertilizer or urea about 15 kg can be applied.
The third fertilization is carried out when the fruit starts to color. This time, the fertilizer should be mainly potassium fertilizer, combined with a moderate amount of phosphorus fertilizer to improve the quality of the fruit, about 15 kg of potassium sulfate per 666.7 square meters, or spray 0.2% of potassium dihydrogen phosphate.
The fourth follow-up fertilizer is carried out after harvesting, mainly phosphorus and potassium fertilizer, with the purpose of restoring tree potential and promoting the maturation of branches and nutrient storage.
Second, two principles of grape fertilization
1, planting grapes can be given solid inorganic fertilizer, the specific type of fertilizer chosen must be based on the growth and development of the grapes. In the early stage, nitrogen fertilizer is mainly applied to promote the growth of branches and vines as well as the development of flowering spikes to prepare for later results.
2. Once the grapes enter the fruiting stage, the amount of nitrogen fertilizer must be reduced and phosphorus and potassium fertilizers can be added to improve the quality of the fruit, the specific amount of which should be adjusted according to the variety, tree potential, ground strength and yield.