Detailed Explanation of Key Techniques for High-Quality and High-Yield Pomegranate Cultivation

1. Cultivation methods

For contiguous planting on hillside land, the forest land should be terraced into level bands to help conserve soil and water. As for planting density, if the climate is warm, rainfall is abundant, the soil layer is deep, and cultivation and management are meticulous, it should be sparser; otherwise, density should be increased. The usual planting density is 4 m × 4 m or 4 m × 3 m, with 40-60 plants per mu (1 mu: 667 sq m, the same below). The best planting time is during the leaf-fall period in autumn, winter, or early spring, and it should be avoided when the weather is dry. Before planting, dig planting holes measuring 0.8 m × 0.8 m × 0.8 m, and apply 50 kg of farmyard manure and 1 kg of superphosphate into each hole. When backfilling soil and fertilizer, it must be compacted layer by layer and filled into a steamed-bun shape to prevent the soil from sinking after planting and the seedlings from being buried too deep. At planting, spread the fibrous roots of the seedling outward in all directions within the hole, then fill with fine soil and firm it, water thoroughly so the roots and soil are in close contact, and then cover the root zone with a layer of coarse soil to help retain moisture. After planting, immediately short-prune the trunk 20-30 cm above a plump bud to promote sprouting from the lower part and the growth of new shoots, and do a good job of trunk training.

2. Management measures

(1) Weeding and mulching. Young pomegranate trees have little growth and weak competitiveness, so after planting, weeds should be removed 3-4 times each year within a 1 m radius around the young trees. Where conditions permit, green manure may be planted between rows throughout the orchard or other crops may be appropriately intercropped, and in summer and autumn the intercrops can be cut and used to cover the root zone to prevent drought. If there is sufficient grass material, covering the whole orchard with a 5-10 cm thick layer is even better. A newly established orchard does not need to eradicate all weeds throughout the orchard, so as to prevent soil erosion and drastic changes in the ecological environment, where excessive fluctuations in temperature and humidity would instead be unfavorable to seedling survival and growth. After 1-3 years of growth and management, the original planting holes have been filled by the root system, so whole-orchard weeding combined with whole-orchard deep plowing should be carried out every 2 years. After 3-4 deep plowings, the soil can become loose. In dry seasons in summer and autumn, attention should be paid to irrigation.

(2) Fertilization. Pomegranate orchards require fertilization at least 2 times per year. The first fertilization is mainly organic base fertilizer, carried out in autumn after fruit harvest. The fertilization standard is about 10 kg per mu for young trees, about 30 kg for middle-aged trees, and about 50 kg for fruiting trees, with an appropriate supplementary application of phosphorus and potassium fertilizers. The second application is in early spring, mainly with a nitrogen, phosphorus, and potassium compound fertilizer, at 0.5-1 kg per tree, for the purpose of promoting sprouting, shoot growth, flowering, and fruit set.

(3) Integrated control of pests and diseases. The pests and diseases damaging pomegranate include pomegranate dry rot and Japanese wax scale, Zhejiang pomegranate stem window moth, leopard moth, yellow stinging moth, pomegranate cling moth, peach fruit borer, peach fruit moth, and others.

1) Dry rot: ① Chemical control. When the disease is found in summer and autumn, spray with 50% thiophanate-methyl wettable powder at 1000 times dilution or with 50% Tuzet wettable powder at 600 times dilution; 1% Bordeaux mixture in equal proportions may also be used at 50 kg per mu, and sprayed again after 7-10 days. ② Prune out and burn or deeply bury dried and diseased plants.

2) Japanese wax scale: ① Chemical control. From the beginning of nymph hatching until before the wax shell is formed, use 50% carbaryl at 500-800 times dilution, or 45% lime sulfur solid formulation at 300-500 times dilution, or 50% dichlorvos emulsifiable concentrate at 800-1000 times dilution, spraying once every 7-10 days for 2 consecutive sprays. ② Protect and utilize natural enemies. There are many kinds of natural enemies of Japanese wax scale, such as parasitic wasps, lady beetles, and lacewings, and attention should be paid to protecting and utilizing them.

3) Pomegranate stem window moth (also called flower window moth): ① Chemical control. At the peak of hatching, spray with 60% dimethoate-metasystox emulsifiable concentrate at 1000 times dilution, or 50% dichlorvos emulsifiable concentrate at 1000 times dilution. After larvae bore into branches, a syringe can be used to inject 400 times diluted dichlorvos into the insect tunnel holes, or a cotton ball dipped in undiluted dichlorvos can be inserted into the bore holes, and the openings of the insect holes should be sealed tightly. ② During the pomegranate growing season, frequently inspect branches, and when damaged new shoots are found, promptly prune off the branch below the last frass-expelling hole.

4) Leopard moth (also called coffee wood borer): ① Light trapping. Adults are phototactic, so black light lamps can be installed in the pomegranate orchard to trap and kill adults. ② Chemical control method. When larvae bore into branches, inject 50% dichlorvos emulsifiable concentrate at 10 times dilution into the holes, then plug the bore holes with mud.

5) Pomegranate cling moth: ① It can be caught manually. ② Spray with 2.5% cyhalothrin emulsifiable concentrate at 4000-5000 times dilution, or 50% dichlorvos emulsifiable concentrate at 1000 times dilution.

6) Yellow stinging moth (commonly known as “itchy hot pepper”): When larvae are found causing damage, promptly spray with 50% phoxim emulsifiable concentrate at 1000-1500 times dilution, or 50% dichlorvos emulsifiable concentrate at 1000 times dilution.

7) Peach fruit borer (also called peach wood borer): ① Fruit bagging. Carry out after the pomegranate grows to the size of a thumb and after the second natural fruit drop. ② Spray for control with 50% phoxim emulsifiable concentrate at 1000 times dilution, or 90% trichlorfon original powder at 800-1000 times dilution.

8) Peach fruit moth: ① During the period when larvae emerge from the soil (June-July), spray the ground around the tree roots with 50% phoxim emulsifiable concentrate at 300 times dilution, and after spraying, shallowly hoe the soil at the edge of the tree. ② During the fruit enlargement period, spray with 80% dichlorvos emulsifiable concentrate at 1000 times dilution.

(4) Rational pruning. Pomegranate is mostly trained in the natural open-center form. Generally, at a trunk height of 25-60 cm, select 3-5 strong-growing branches with evenly distributed orientations and a certain distance from one another (about 20-30 cm) and spread them out as main branches; overly long ones should be appropriately shortened or promptly pinched, and surplus ones should be thinned out. Thereafter, on the left and right sides of the main branches, every 60-80 cm, retain secondary main branches or side branches, remove the remaining strong branches, and keep weak branches and drooping branches as auxiliary nourishing branches.

Pomegranate tends to sprout easily at the root crown, and these should be removed at any time. In winter, prune out diseased and pest-infested branches, dead branches, slender branches, and densely growing branches, and cut back and shorten crossing branches, water sprouts, and the like. In summer, use measures such as branch bending, pinching, and girdling to control the canopy and increase yield, and note that too many fruits should not be retained.

4. Harvest

Pomegranate fruits do not ripen uniformly and need to be harvested in batches. On rainy days, because water accumulates inside the fruit and easily causes rot, harvesting should not be done; it is best to harvest before rain to prevent fruit cracking when rain occurs.