First, the "three sprays" of flowering period: jujube trees have a long flowering period, which can be divided into three periods: initial flowering period, full flowering period and final flowering period, which can last for more than one month, that is, from late May to the end of June, and generally enter the full flowering period around June 8. Jujube prefers wet to dry in flowering period, but at this time, the weather is hot and dry, and there are many sandstorms, which is easy to reduce the density of jujube stigma leaves and make the stigma stick with a lot of dust, which seriously affects normal pollination. At the same time, due to the harm of dry and hot wind, the transpiration of jujube trees increased. At this time, if there is lack of fertilizer and water, it is easy to wither and fall off the stigma. Therefore, spraying drugs, fertilizers and water at flowering stage can greatly improve the fruit setting rate of jujube trees. When 30% of the flowers are in full bloom, gibberellin, zuoguoling, 2,4-6 can be sprayed at the concentration of10× 10-6 to 15× 10-6 before the sunny and windless morning. 2-0。 The effect of 3% borax solution is better. In the full flowering period, when 60% of the flowers are in bloom, water 1 time is evenly sprayed on the jujube flowers every 2-3 days, for a total of 2-3 times, which can improve the fruit setting rate by 35-48%. Spray 0 when the jujube blossoms are 40% open. 5% urea and 0. 4% potassium dihydrogen phosphate solution, sprayed/kloc-0 every 5-7 days, generally sprayed continuously for 3 times, can improve the fruit setting rate by about 30%; Spraying 1 time in mid-July can reduce physiological fruit drop. If it rains after spraying, it should be sprayed again in time.
2. Reasonable pruning: Pruning jujube trees can adjust tree vigor, make full use of nutrients, ensure ventilation and light transmission of jujube trees, increase the number of fruiting parts, and reduce rotten fruits and fruit drop, thus achieving the purpose of increasing production. Jujube pruning is mainly based on thinning, combined with shearing and shrinking. We should do this: sparse dense branches, remove horizontal branches, cut off drooping branches, compress too high branches, slightly shrink strong trees, then shrink weak trees, properly remove old branches from old trees, and trim young trees around them. Pruning should be done after beginning of spring and before jujube tree sprouting.
Third, timely nail opening: nail opening is annular peeling. Nail opening can inhibit vegetative growth, prevent jujube witches' broom, improve the nutritional conditions of jujube flowers and young fruits, and make them fall less and sit more. Therefore, there is a saying in the agricultural proverb: "Cut a few knives when flowering, and jujube trees bend over". Jujube trees can increase production by about 30%. Nailing should be carried out when the jujube tree blooms for one third, and it should be opened 30-40 cm above the ground with a width of 0. 5-0。 7 cm is suitable, the depth reaches xylem, but it can't hurt xylem cambium. The edge of the knife should be smooth, and no stubble can be left. After opening, apply an appropriate amount of pesticide to the nail mouth to prevent pests. Jujube trees with a tree age of less than 7 years, a trunk diameter of less than 10 cm, or not robust should not be opened. The nail opening part should be replaced year by year.
4. Pinch new branches: Pinch new branches can control the uncoordinated growth of jujube tree crown, which is beneficial to form a reasonable crown, make the density of branches uniform, have good ventilation and light transmission performance, control the unnecessary growth of branches, save nutrients, and help improve the fruit setting and fruit development of jujube trees. The experiment proved that the maximum length of new branches in jujube orchard after coring can reach 45 cm, and the maximum number of fruits can reach 12, which is large and full. The longest jujube orchard without pinching on a branch is only 25 cm, and it bears up to 5 fruits. Pinch the heart should be in the bud stage of jujube branches in the middle and late May, and select new branches with a length of 5-7 cm that grow in the dense branch area of jujube trees that year.
5. Fertilization and watering: jujube trees need water and fertilizer at the early and late flowering stages. Generally, applying cake fertilizer 15 kg, ammonium bicarbonate 1 kg or 50 kg of human excrement to each tree at the early flowering stage, and applying urea 1 kg or compound fertilizer 1 kg at the late flowering stage can significantly improve the yield. The application method is: dig a deep annular ditch with a width of 40 cm at a distance of two meters from the trunk, sprinkle fertilizer, fill it with water, and fill it up after water permeates.
6. Release bees when flowering: Jujube is a typical insect-pollinated flower, which cannot be pollinated by itself or by wind, but its nectar is rich and fragrant, and bees are the best pollination medium. During the flowering period, beehives are evenly placed in the jujube garden, and the spacing between beehives is not more than 300 meters. Bees began to move at 1 1℃ and were most active at 16-29℃. Using bees to collect pollen and pollinate can greatly improve the fruit setting rate. However, it is forbidden to use carbaryl and pyrethroids which are highly toxic to bees in the process of releasing bees in jujube orchards.