What are the fertilization time and application rates for citrus?
Citrus is a very popular fruit, and its planting area in our country is very large. When growing citrus, we need to pay attention to doing a good job of fertilization, as fertilization is the key to ensuring that the nutritional needs of citrus growth are met. When fertilizing, we must first understand the fertilizer requirements of citrus and properly control the fertilization time and application rates. So below, the editor will introduce the fertilization time and application rates for citrus. Let's take a look!
1. Fertilizer requirements
According to professional survey data, when growing citrus, for every 1000 kg of fruit produced, the proportion of nitrogen and potassium fertilizer is the highest, followed by phosphorus fertilizer, and finally nutrient elements such as calcium and magnesium. The ratio of nitrogen, phosphorus and potassium should be controlled at about 1:0.3:1.3. The nutritional needs of citrus will constantly change with the growth stage of the citrus. The absorption of nitrogen, phosphorus and potassium by growing citrus begins to increase rapidly in spring, reaching a peak demand period around June. It then begins to decline in autumn, and after winter, the absorption of nitrogen, phosphorus and potassium nutrients stops.
Generally starting in April in spring and continuing until October, this is the peak period of nutritional demand for citrus trees. If fertilization is improper, the harm caused to citrus trees is very great. For example, when the spring buds of citrus trees sprout, if there is too much nitrogen fertilizer, it can easily cause excessive vegetative growth of spring shoots, leading to a lower fruit-setting rate. If nitrogen fertilizer is excessive in the later stage, it will continuously produce late autumn shoots, making it impossible for the citrus to overwinter safely. However, during the fruit expansion period, citrus has a relatively large demand for nitrogen fertilizer. If nitrogen fertilizer is lacking at this time, it will worsen physiological fruit drop, and both quality and yield will be greatly affected.
2. Fertilization application rates
When fertilizing citrus trees, the application rate is very important. The fertilization application rate for citrus trees should be properly controlled according to the fruit load of the tree, tree age, variety, soil and various other conditions. Under normal circumstances, if the yield of citrus per mu is 2500 kg, then the nitrogen fertilizer application rate should be controlled at about 30 kg, phosphorus fertilizer at about 15 kg, and potassium fertilizer should also be maintained at 30 kg. A reasonable fertilization rate is the key to ensuring normal growth of citrus. Be careful not to apply too much fertilizer, so as to prevent the opposite effect.
3. Fertilization time
The first fertilization should be applied half a month before spring sprouting or when the spring shoots turn green. Applying it too early or too late will have a relatively large impact on the growth of citrus trees and fertilizer efficiency. Then, after citrus stops dropping fruit, apply fruit-strengthening fertilizer, generally in August each year. The ratio of nitrogen, phosphorus and potassium in fruit-strengthening fertilizer should be given equal importance. Especially during fruit expansion, the proportion of potassium should be appropriately increased to promote fruit expansion and flower bud differentiation. Then, before and after fruit harvesting, apply post-harvest fertilizer. Control the application time according to the variety. Early-maturing varieties can be fertilized while harvesting, while late-maturing varieties should be fertilized one week before harvest.
The above is a brief introduction to the fertilization time and application rates for citrus. That is all for today's introduction. This article is for reference only, and I hope it can help everyone!