Maintenance management and pest control of Lagerstroemia indica

Insufficient sunshine and lack of fertilizer. Main points of cultivation (1) Generally, transplanting Lagerstroemia indica is in the beginning of March-April, and Tomb-Sweeping Day is the best, followed by autumn. When transplanting plants, you should bring soil balls. It can also be transplanted in the growing season, but before transplanting, all the new branches and leaves of the year should be removed, and soil balls should be brought, and the soil should be kept moist after planting, so that it can survive. (2) Water Lagerstroemia indica needs moist soil in the growing season. Water 1~2 times before germination in spring, and keep the soil moist during the growing period. Fertilization Lagerstroemia indica likes fertilizer, and adequate fertilizer is the key to more pregnant buds and good flowering. In early spring, basal fertilizer should be applied again, which is the guarantee of more flowers. Topdressing should be carried out in May-June to promote the growth of flower buds. The use of fertilizer should be mainly decomposed human manure or cake fertilizer, and chemical fertilizer can also be applied as appropriate. (3) Pruning and shaping Lagerstroemia indica in winter. The principle of pruning is that branches are evenly distributed to form a complete crown. Cut off the branches that affect the crown, and the remaining branches are about 1/3 from the top of the crown, which can achieve the effect of full trees and flowers. Lagerstroemia indica has strong tillering ability, so it is necessary to cut off the tillers on the trunk and branches in time to ensure the formation of a full crown. Lagerstroemia indica is resistant to pruning, the branches are flexible, and the cambium between branches is easy to heal, so it is easy to shape. In plastic surgery, it can be cut into various tree shapes, such as Gao Qian tree shape and low-stem round head shape. In terms of modeling, Sichuan often plants Lagerstroemia indica seedlings side by side in rows with a spacing of about 20 cm. Then cross-weave the seedlings, tie them tightly with ropes, and heal after several years. After the ropes are removed, they are tied together to form vases, arches, pavilions, bridges and other shapes. In addition, several crape myrtle plants were planted in close rows and juxtaposed, and after years of healing and shaping, a simple and natural pile scene was formed. (4) Lagerstroemia indica has a long flowering period, but it has reached the end of flowering in late September, at which time the color and flower shape are not ideal. In order to make the National Day holiday more beautiful and let Lagerstroemia speciosa bloom in the "Eleventh", the apex of the flowering Lagerstroemia speciosa can be cut short in early August, and all the flower branches and the sharp branches of about 1/3 can be cut off. After that, it is necessary to strengthen fertilizer and water management, fertilize the soil for 2-3 times, keep the soil moist, and pay attention to pest control. Generally 1 month can form flower buds with new buds. 4. What are the breeding methods of Wei Zi (1)? Lagerstroemia indica can be propagated by sowing, cutting and dividing plants. (1)10 ~11Sowing, picking capsules, drying, cracking, peeling and cleaning seeds. Sow in the sand bed from February to March in the following year, cover with thin soil, keep the soil moist, and seedlings can emerge in April. ② Cuttings are carried out in spring and summer. In spring, before germination, select robust branches of 1~2 years old, cut cuttings with a length of about 15~20 cm, and insert them into the soil for 2/3. It is best to insert loose and well-drained sandy loam. (3) Digging out new plants from the rhizosphere with Castanopsis carlesii in early spring and planting them separately. (2) How to control the common pests and diseases of Lagerstroemia indica? ① soot disease: it is more common on leaves and branches, and can be sprayed with 40% omethoate EC 1500 times or 80% dichlorvos EC 1500 times. ② Powdery mildew: 70% thiophanate-methyl wettable powder 800 times solution or 25% triadimefon 800 times solution can be sprayed 3-5 times at the initial stage of the disease, which can be prevented and cured. ③ Lagerstroemia indica: 25% phoxim EC with 0/000 times of/kloc or 40% omethoate EC with 0/500 times of/kloc can be sprayed. It is best to spray the medicine when the larvae are covered with wax powder, and the effect is remarkable. In addition, brushing off the overwintering insects in the cracks of the bifurcated river in winter can reduce the harm in this spring. ④ Big decline moth: Remove the protective capsule. Spraying 90% trichlorfon 1000 times solution when hatching larvae appear in early May and June has a good effect.