How to control shoot growth in lychee? Detailed explanation of the key points of shoot control techniques
Shoot control and flower promotion in lychee is a very important management task when growing lychee. Whether it is done well or poorly directly affects the amount of flowers and fruit the lychee tree produces the following year. Therefore, we must pay attention to controlling the timing of shoot control in lychee and do the shoot control work well. Generally, shoot control in lychee should be carried out after the autumn shoots have matured. So how exactly should it be done? Below, the editor brings you the shoot control techniques for lychee. Let's take a look!
1. Use potassium to control nitrogen
For shoot control in lychee, we first need to use the method of using potassium to control nitrogen to promote flower bud differentiation. This is because when the lychee tree is undergoing flower bud differentiation, its demand for potassium is very high. So after the last shoots turn green, we should appropriately apply an additional potassium fertilizer. Moreover, potassium fertilizer has a certain inhibitory effect on nitrogen fertilizer and can prevent the lychee tree from absorbing too much nitrogen. In this way, we can also achieve the goal of controlling winter shoots, but we must also pay attention to controlling the application amount. If the fruit load on one tree is 50 kg, then the application amount of potassium chloride is generally around 0.5-0.7 kg.
2. Deep hoeing to cut roots
After the last autumn shoots of the lychee tree have matured, we should combine this with orchard cleanup work to carry out deep hoeing to cut roots. First, the topsoil should be loosened with a hoe at a position about 30 cm from the main trunk of the lychee tree, from shallow to deep, cutting the floating roots on the surface of the tree, with the deepest hoeing reaching about 20 cm. But if it is an old tree, then care must be taken not to hoe too deep. This avoids excessive root damage and weakening the tree's vigor. When deep hoeing, a ring-shaped trench can be dug to cut some of the tree's lateral roots, and then backfilled after about 20 days. Also sprinkle in an appropriate amount of lime powder to control root absorption and inhibit the growth of winter shoots.
3. Ring girdling and ring stripping
When the lychee tree's autumn shoots transition to the flower bud differentiation stage, the leaves will gradually lose their green color, which is a sign of flower bud differentiation in the lychee tree. However, because some trees absorb too much nitrogen fertilizer, they do not lose green color normally during flower bud differentiation, so at this time ring girdling and ring stripping are needed. Ring girdling should be done according to the lychee variety and tree vigor, with about two rings cut, 4 cm wide, in a spiral cut. Ring stripping, on the other hand, requires cutting away a certain width of bark, and closed-loop stripping should be avoided as much as possible. If the tree is weak in growth or is an old tree, then ring girdling is not suitable, and the timing should be after the autumn shoots have matured and before flower bud differentiation.
4. Manual removal
In late autumn, if the temperature is warmer and there is more rain, then the lychee tree is very prone to sprouting winter shoots. Especially for young trees and vigorous trees, the winter shoot phenomenon is very common. If the tree is not large or few winter shoots have sprouted, then we can carry out manual removal. Winter shoot removal should also be carried out before flower bud differentiation to avoid affecting flower bud differentiation. When the winter shoots grow to about 5 cm, remove them at the position of the first pair of compound leaves, keeping only about 1 cm of young shoot, and then appropriately spray twice with a shoot control and flower promotion agent.
The above is a brief introduction to lychee shoot control techniques. That is all for today's introduction. This article is for reference only, and I hope it can help everyone!