The correct method and precautions for girdling longan trees
Longan is extremely popular with consumers in the market and delivers very high market returns, and in the process of growing longan, girdling is indispensable if you want to increase yields. It is a relatively safe and effective measure for promoting flowering and protecting fruit, suitable for result trees that grow on the vigorous side, and it also works fairly well on young trees. So what is the best way to girdle longan? How should it be done? Follow the editor to learn more about it.
1. The role of girdling
Longan trees often drop a large amount of fruit during the young fruit stage. This is because flowering consumes a large amount of nutrients, causing a nutrient deficit in the tree, and on top of that the root system is at its growth peak and competes for a large share of nutrients, while the nutrients produced by leaf photosynthesis are insufficient, so the fruit cannot get enough nutrients to grow, leading to heavy fruit drop. To reduce longan fruit drop, you can use pruning or flower and fruit thinning as well as light girdling to ensure the nutrients needed for fruit growth, thereby achieving the goal of improving the fruit set rate.
2. Girdling time
When girdling longan trees, the timing must be grasped properly. For weak trees, girdling too early, if low-temperature and dry conditions follow the girdling, will inhibit root extension and greatly weaken the root system's absorption of fertilizer and water, and in severe weather it can also cause leaf drop. In addition, if rainy and sufficiently sunny weather follows the girdling, the wound will heal quickly, unable to block the upward transport of nutrients, and the plant will grow vigorously, so the later effect of controlling excessive shoot growth cannot be achieved. For vigorously growing plants, girdling too early will affect the physiological differentiation of flower buds and ultimately affect the yield, so longan trees should be girdled around the winter solstice according to the strength of the tree's vigor.
3. Girdling method
For longan girdling, you should choose a girdling knife with a sharp blade. If it is not sharp, the sieve tubes in the depressions of the trunk cannot be cut, forming a “bridge” phenomenon, and the girdling effect is poor. If the blade is not thin or the edge is not sharp, work efficiency is low, the girdling wound is severely crushed, healing time is prolonged, and the tree's vigor is weakened too much; in severe cases the old leaves turn yellow and drop early, and even bark splitting occurs. When girdling, make one ring cut around the trunk or a spiral cut of 1.25 turns, with the depth reaching the cambium but not injuring the xylem. The girdling spacing must not be less than 2 cm, otherwise the root system will be over-starved, causing the tree to decline too much and making it difficult to remedy.
4. Precautions
After the plant is girdled, the root system's ability to absorb fertilizer and water decreases, so at this time sufficient water should be maintained, and fertilizers should mainly be organic fertilizers. During consecutive overcast and rainy days, in order to prevent the root system from being over-starved, foliar fertilizer should be sprayed promptly. Longan cannot be girdled at any time; it should be done according to the growth conditions of the longan tree, and within 1 year it can only be girdled 1~3 times. The appearance of old leaves turning yellow and dropping and long-term decline 1-2 months after girdling is a normal phenomenon.
The above is an introduction to the longan girdling method and precautions. We hope it can help you. If you want to learn more related knowledge, please stay tuned to us.