We now introduce the longan cultivation and management techniques for high and stable yields

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1. Fertilization

Fertilization is the main content of soil management for adult fruit trees. It is a basic measure to increase and stabilize yields and overcome the phenomenon of large and small annual fruit

. It should be based on longan. According to the growth condition of the tree, apply sufficient fertilizer in stages and in a timely manner to fully meet its growth and fruiting needs. When adult trees have sufficient fertilizer sources, they can follow changes in tree growth, flowering and fruiting. In the past, they were required to fertilize 4 to 5 times throughout the year. I think the following three rhizosphere fertilizations

That's enough.

(1) Rhizosphere fertilization

1. Pre-flowering fertilizer (flower-promoting fertilizer) is applied from the end of December to mid-to-late January to promote healthy flower spikes

Strong, well-developed flower organs. Fertilizer application amount: Based on 100 jins of fruit produced per plant, 1-2 jins of compound fertilizer should be applied to each plant.

50-100 jins of composted farmyard manure plus 1 jin of peanut bran powder. Compound fertilizer should be applied by drench or withdrew after rain.

Farmyard manure and peanut bran powder should be spread around the crown in the rhizosphere. It would be more ideal if a 50 cm deep annular trench can be opened around the crown of the tree and the weeds should be fertilized together. The fertilization period should be based on the tree vigor, leaf color depth

and rainwater, etc. The time will depend on the situation. If the tree is strong and the leaves are green, or the weather warms up early or there is a lot of rain, it is generally not advisable to apply early. On the contrary, if the tree is weak or the weather is cold or the hormone spray control is too heavy, then

fertilization should be done earlier.

2. Fertilizer to strengthen flowers and fruits is applied after the flower spike skeleton has been formed and before the second physiological fruit drop. The purpose is to timely replenish the nutrients of the tree in the late flowering period. Ensure the nutrients needed for the growth and development of young fruits, reduce the second physiological fruit drop, promote fruit enlargement, and increase the current year's yield. It lays the foundation for growing autumn shoots after harvest and cultivating good fruit-bearing mother branches. Amount of fertilizer: Apply 50--100 jins of machine fertilizer per plant (based on 100 jins of fruit produced) (if pre-flowering fertilizer has been applied, less fertilizer can be applied when the fertilizer source is insufficient), 1-100 urea -2

catties, calcium magnesium phosphate fertilizer 2--3 catties, potassium chloride 2--3 catties, peanut bran powder 2-3 catties, magnesium sulfate 0.3

- 0.5 catties , spread evenly under the canopy drip line, cover with straw and pour water in time.

This time, fertilizer can be applied less or not at all depending on the tree condition and leaf color.

3. Fertilizers before (and after) fruiting are generally based on quick-acting nitrogen fertilizers. In particular, late-acting fertilizers or granular fertilizers should be avoided.

Materials such as insoluble compound fertilizers are not good for fruit trees. Early absorption. The role of this fertilizer is to increase yield

, reduce late fruit drop, restore tree vigor, reduce leaf drop after fruit picking, timely promote autumn shoot growth, and cultivate

good results. The mother branch is very effective in reducing the phenomenon of large and small annual fruiting and achieving high and stable yields every year.

10--15 days before fruit picking, apply decomposed peanut bran water or dung water 20 times in the canopy drip line area

Add urea 1--2 times 0-300 catties Jin, 1.5-3 Jin of easily soluble compound fertilizer, 30-50 grams of borax. If

if the fertilizer cannot be applied on time this time, it must be applied within seven days after picking the fruit. Use decomposed flowers as fertilizer

raw bran water or dung water 200-300 Add 2 to 3 pounds of ammonium bicarbonate, 2 pounds of potassium chloride, 1 to 2 pounds of phosphate fertilizer, and 30 to 50 grams of borax.

If the climate is dry, water must be poured or irrigated in time to ensure that the autumn shoots are extracted in time after picking.

The above three fertilizations are very necessary, especially the first and third times, which must be carried out as required.

(2) Top dressing outside the roots

Every time you spray, you can add some foliar fertilizer. It is recommended to use Yuhualing organic nutrition series products

and use as little inorganic chemical fertilizers as possible.

2. Plastic pruning

(1) Pruning of young trees

The purpose of plastic pruning is to cultivate a tree shape with high and stable yields. Plastic surgery should start with young trees and with planting. Fixed trunk: When planting, leave the main trunk 50--70 cm high. After the planting is successful, select 2--3 main branches with strong growth and reasonable orientation on the main trunk as first-level branches. When the first-level branches grow to 50 cm

, pinch at 40 cm. Similarly, select 2-3 branches on the first-level branches as second-level branches. Same as

The sample method retains third-level branches and fourth-level branches. Make branches at all levels extend evenly around to form an open

round-headed crown.

(2) Pruning of adult trees

The purpose of pruning adult trees is to maintain strong tree vigor and cultivate good fruit-bearing mother branches. Pruning is usually carried out in spring, summer and autumn. Spring pruning mainly involves cutting off overly dense branches, weak branches, diseased and insect-infested branches, and combining

sparse flowers. Summer pruning is carried out in June-July to remove overly dense branches, diseased branches, thin and drooping branches, and to thin out the fruits.

Autumn pruning is mainly carried out after picking fruits. This is a delicate pruning work. It mainly removes dead branches, diseased branches, shade branches and overly dense branches, and removes excessively dense branches. In summer and autumn, cut off some

parts of the shoots, leaving 1-2 branches with strong growth and reasonable distribution on each base branch to concentrate nutrients and promote

fruiting Branch growth is substantial.

3. Disease and Pest Control

(1) Longan “broom disease” is also known as bald branch disease, arbusculus disease, broom disease, etc. The pathogen is a virus that is transmitted through grafting or insect infestation. After the young shoots of the diseased plants are damaged, the young leaves become narrow and bent, the leaf edges are curled, cannot be expanded, and the leaf color is light green. Diseased leaves show various deformities and fall off easily. The leaves on the diseased tips dry up and fall off.

The branches become bare. Sometimes there are clusters of new shoots, and the internodes are shortened and broom-shaped. Injured flower spike nodes are shortened

and the flower spikes form clusters or clusters, unable to bear fruit normally, the diseased tree will weaken, the yield will decrease, and

eventually the whole tree will die.

Prevention and control methods:

1. Focus on prevention, strengthen cultivation management, especially water and fertilizer management, increase application of organic fertilizer, and timely

Prevent and control psyllids and stink bugs Pests such as crickets, white moths and wax cicadas.

2. Cut off diseased branches in time, burn the diseased branches together and spray dicofol 800--1000 times,

Spray twice.