Five key management measures for post-harvest lychee care
In May and June, some early-maturing lychee varieties are soon harvested, and it is time to enter the post-harvest management period. Fruiting consumes a large amount of nutrients in lychee, and picking the fruit damages the branches, giving the tree a kind of "internal injury." Therefore, timely management after harvest is needed so the lychee can be replenished with nutrients early and lay the foundation for a bumper crop next year. Otherwise the tree...
In May and June, some early-maturing lychee varieties are soon harvested, and it is time to enter the post-harvest management period. Fruiting consumes a large amount of nutrients in lychee, and picking the fruit damages the branches, giving the tree a kind of "internal injury." Therefore, timely management after harvest is needed so the lychee can be replenished with nutrients early and lay the foundation for a bumper crop next year. Otherwise, the tree vigor cannot recover in time, the autumn shoots will not grow well, and next year there will certainly be no high yield. How should post-harvest management be carried out? There are mainly the following five aspects:
I. Clearing the orchard
The first thing to do after harvest is to clean the lychee orchard once, achieving the "three clearings": First, clear away dead branches and fallen leaves. Collect all dead branches, fallen leaves and fallen fruit in the orchard, gather them and burn them to eliminate pests and diseases and prevent them from accumulating and causing harm. Second, clear away weeds in the orchard. Weeds in the orchard that both rob fertilizer and attract insects must be thoroughly cleared away, so that weeds do not compete for the fertilizer applied to the lychee. Third, clear away garbage in the orchard. Garbage in the orchard that cannot be used as fertilizer should be cleared out of the orchard to keep the lychee orchard clean and give the lychee a good growing environment.
II. Spraying pesticide
After clearing the orchard, spray the tree bodies and the ground thoroughly once. There are many pests and diseases that harm lychee, especially after this spring and the flowering and fruiting stages of lychee, the types and numbers of pests and diseases that have accumulated are very great, and spraying during the flowering and fruiting period is also subject to certain restrictions. Therefore, after harvesting and clearing the orchard, spray one insecticide and fungicide application according to each of the main pests and diseases that occurred during the fruiting period, or mix them and spray once, such as 2.5% Kung Fu emulsifiable concentrate at 2000 times plus Jinlei Duomier water-dispersible granules at 750 times, etc., to reduce the accumulation of pest and disease sources, reduce harm, and protect the normal growth of lychee.
III. Pruning
After a year of growth, the tree body will grow many useless branches, and they also consume nutrients. Therefore, after harvest, prune the lychee once, cutting away shade branches, crossing branches, overly dense branches, water sprouts, overlapping branches, diseased branches, slender branches, dead branches, etc. one by one, to reduce nutrient consumption, make the lychee tree shape beautiful and scientific, grow into a high-yielding canopy, and lay the foundation for a bumper crop next year.
IV. Fertilizing
After harvest, applying fertilizer reasonably to the tree body is especially important. Fruiting consumes a large amount of nutrients in lychee, especially in high-yielding trees. In order to quickly restore tree vigor and enable normal, robust growth, this fertilization work must be taken seriously and not done carelessly. After harvest, fertilization should be mainly nitrogen fertilizer, with phosphorus and potassium fertilizer applied together. According to the experience of relevant fruit growers, the nitrogen fertilizer application amount accounts for 50% of the whole year, phosphorus fertilizer 33%, and potassium fertilizer 25%. In order to maintain long-term fertilizer efficiency, more organic fertilizer should be applied, together with quick-acting nitrogen fertilizer. For organic fertilizer, it is best to dig trenches 60 cm deep and 50 cm wide at the drip line around the outer edge of the canopy or between rows, and apply green manure, leaves, weeds and farmyard manure, human and livestock manure, etc. in layers, to ensure long-term fertilizer efficiency.
V. Drainage and irrigation
The growth characteristics of lychee mean it needs a certain amount of water but also fears being waterlogged. According to the actual conditions of the lychee orchard, drainage and irrigation work should be done well. Lychee orchards in low-lying areas should do a good job of digging ditches for drainage, especially in summer, when rainstorms often occur. If drainage is poor, the lychee orchard will accumulate water and become waterlogged, causing a lack of oxygen in the soil, making root development poor and affecting growth. However, summer is also a high-temperature season, and lychee orchards on high, dry land are very prone to drought. At this time, attention should be paid to irrigation to prevent lychee trees from lacking water and suffering drought. Where there is a water source, water can be diverted into the orchard for irrigation; where there is no water source, water should also be carried to sprinkle and irrigate, so as to maintain the normal growth of lychee trees.