A、The growth cycle of lychee
The annual growth cycle of litchi can be divided into the following three distinct growth stages. Each stage has its own special growth center and the corresponding fertilization requirements. In the cultivation and management of the resultant litchi tree, especially in the fertilization of lychee . Should be based on these three stages, reasonable arrangements for fertilizer types, fertilization methods. This can ensure high quality and sustained high yield of lychee.
B、The characteristics of lychee fertilizer needs
In the three growth and development stages of lychee. Because of the different growth and development centers of lychee. Therefore, the nutritional characteristics of each stage are different. In other words, in these three stages, the lychee fertilization, to the growth and development of the characteristics of the center, choose a different fertilizer. As it happens, these three stages happen to have relatively obvious differences in the needs of the three elements of nitrogen, phosphorus and potassium.
The first stage requires more nitrogen, supplemented by phosphorus and potassium. The second stage requires more potassium and phosphorus, supplemented by nitrogen. The third stage requires more potassium and nitrogen, supplemented by phosphorus. Therefore, the above three stages of growth and development corresponds to the three nutritional stages of lychee.
Each nutritional stage has different requirements for the three elements of nitrogen, phosphorus and potassium. Although the focus of the elements required at each stage is different. But farmers must remember not to be mistaken that a nutrient stage requires only one element of fertilizer. This misconception is often found in production. In fact, at each nutritional stage, a compound fertilizer with different ratios of nitrogen, phosphorus and potassium should be applied. At present, the market with more compound fertilizer, is produced by the company Nagric.
C、How to lychee reasonable fertilization
Now farmers have learned that the results of the annual growth cycle of the lychee tree has three nutritional stages. These three stages are: nitrogen-based nutrients to cultivate the nutritional stage of the fruiting mother branch; potassium and phosphorus-based bud cultivation and flower promotion, flower preservation nutrition stage; potassium and nitrogen-based nutrition stage of fruit growth and development.
1、The first nutritional stage of lychee
At present, the lychee is in the nutritional stage of cultivating the fruiting mother branch. How to select fertilizer fertilizer according to the stage of nutritional characteristics, is an important part of the cultivation of the mother branch. The result of the mother branch generally draws 2 to 3 batches. The result of the mother branch draw period, not only to restore the last season of lychee growth consumed tree nutrients, but also to supply a lot of nitrogen, phosphorus and potassium nutrients to promote the early growth of autumn tips.
At this time suitable for the use of high nitrogen compound fertilizer. Such as nitrogen, phosphorus and potassium ratio of 25-5-10 humic acid compound fertilizer, or other high-nitrogen compound fertilizer. The amount of each tree is 2 to 3 kg. If the year the amount of lychee fruit is small, the amount of fertilizer can be less. If the year lychee fruit is particularly large, then the amount of fertilizer should be increased. Otherwise, it will not draw new tips, but also cause the next year’s small year. Fertilization time is generally appropriate 1 to 2 weeks after the harvest. If now not to tip, you should add a high amount of nitrogen compound fertilizer, fertilizer after watering, so that you can promote late autumn tips.
2、The second nutritional stage of lychee
In early December, when the last batch of tips matured. Farmers in order to promote bud differentiation and flower promotion, flower preservation, it is recommended to apply high phosphorus and potassium compound fertilizer. For example, a 1:3:3 nitrogen, phosphorus and potassium compound fertilizer. There is a lack of such high phosphorus and potassium compound fertilizer in China. So we can use a small amount of 1 pound of 15-15-15 nitrogen, phosphorus and potassium compound fertilizer, mixed with 2 pounds of 15% calcium superphosphate, mixed with about half a pound of 50% potassium sulfate, and mix it well. This mixture is the 1:3:3 compound fertilizer. Apply 0.5 to 1 kg of this mixed fertilizer per tree, and pour the right amount of water at the fertilizer application. This facilitates the differentiation of flower buds.
3、The third nutritional stage of lychee
In about March, after the flowering fertilizer. The purpose is to preserve the fruit and promote the expansion of lychee fruit. At this time should use high potassium, nitrogen in the middle, a small amount of phosphorus compound fertilizer. Such as 10-6-24 humic acid compound fertilizer. At this point, if we observe weak growth of lychee, we recommend using a high potassium compound fertilizer with slightly higher nitrogen. Such as 16-5-19 humic acid compound fertilizer. Apply 1.5 to 2 kg per tree. This application of nitrogen in the fertilizer is conducive to fruit expansion, potassium in the fertilizer is conducive to fruit accumulation of sugar and prevention of fruit cracking.
Here to emphasize the point is that each application of fertilizer should be combined with the right amount of irrigation. Otherwise, it is based on the nutritional characteristics of lychee, want to promote the autumn tips of ripening, bud differentiation and flowering, fruit expansion and high quality yield through fertilization. However, if not irrigation or just rely on God’s rain and fertilizer effect, then the above three stages of fertilization can not play in a timely manner. Even, without timely irrigation, it is possible that the fertilizer remains in the soil for a long time. When the lychee does not need fertilizer, and it happens to rain, then the residual fertilizer in the soil will play a fertilizing effect, which may cause wash tips, wash flowers, poor fruit growth and other phenomena.
Of course, we worry that the application of high phosphorus and potassium fertilizer before overwintering, combined with irrigation will wash out the tips. In fact, the recommendation here is only to irrigate the fertilizer in the right amount, as long as the amount of irrigation water is just enough to dissolve the fertilizer. This allows the phosphorus and potassium to play a role in promoting and preserving flowers, without too much water causing flushing of the tips.