Never relax management after harvesting large cherries
Large cherries in Shaanxi are basically harvested by May-June, and management is often relaxed after harvest. You should know that it is precisely after harvest that the effective period of cherry flower bud differentiation occurs. Balanced and timely nutrient supply to the tree plays a very important role in restoring tree vigor and forming flower buds. In the main cherry production areas of Baqiao in Xi'an and Tongchuan, growers all have rich experience...
Large cherries in Shaanxi are basically harvested by May-June, and management is often relaxed after harvest. You should know that it is precisely after harvest that the effective period of cherry flower bud differentiation occurs. Balanced and timely nutrient supply to the tree plays a very important role in restoring tree vigor and forming flower buds. In the main cherry production areas of Baqiao in Xi'an and Tongchuan, growers all have rich experience, but in most areas management is still relaxed and treated like ordinary fruit trees, resulting in few or even no fruit. Based on investigation, the author puts forward suggestions for cherry growers' reference:
1. To promote flower bud differentiation, timely topdressing is needed: after fruit harvest is the period of greatest nutrient consumption in a cherry's life. Post-harvest fertilization supplements nutrients, and strong tree vigor makes it easy to form flower buds. Besides nitrogen, phosphorus, potassium, and medium and trace elements such as magnesium, boron, zinc, silicon, and iron are extremely important for flower formation. Based on the soil nutrient status in Shaanxi, for many years mainly nitrogen fertilizer and phosphorus fertilizer have been applied, while potassium fertilizer and medium and trace elements have been neglected. Nitrogen should be controlled, phosphorus reduced, and potassium supplemented. Choose organic fertilizer and biological fertilizer, bacterial fertilizer, and organic-inorganic biological fertilizer combining all three. First apply sufficient organic fertilizer. Calculated at 1 jin of fertilizer per 1 jin of fruit, for a yield of 1000 kg per mu, 1000-1500 kg of organic fertilizer should be applied, plus Longfei Dasanyuan organic-inorganic biological fertilizer, which contains 20 million beneficial bacteria, 20% organic matter, 20% nitrogen, 5% phosphorus, and 20% potassium. Supplement medium and trace elements with Wotianjia to achieve full-nutrient fertilizer supply. It is recommended to apply 2-2.5 kg of Dasanyuan fertilizer per tree, plus 1.5-2 kg of Wotianjia fertilizer per tree. For large trees nationwide with canopies at full fruit stage, broadcast application or radial trenches 30 cm wide and 20-40 cm deep, mix with soil after application, cover with topsoil, and carry out border irrigation.
For foliar spraying, choose Guoyou amino acid or Shuofeng 481 foliar fertilizer, dilute to 600 times and spray evenly on the leaf surface, leaf underside and branches. You can also add 0.2% borax and spray the whole tree to supplement nutrients and promote flower bud formation. Foliar fertilizer once every 10 days can be used frequently during the growing season with benefits and no harm.
During the growing season, nitrogen fertilizer should not be applied too much. Too much nitrogen causes excessive vegetative growth, making it very difficult to form flower buds.
2. Do summer pruning well: the physiological differentiation of cherry flower buds occurs after harvest, while morphological differentiation is completed about 2 months after harvest. In addition to balanced fertilization and regulating tree vigor, balanced pruning is also very important for flower formation. Only when reproductive growth and vegetative growth are balanced and nutrients complement each other is it important for promoting flowers. Only after reproductive growth is completed can flower buds form. From the perspective of summer pruning, the main technical measures commonly used in cherry pruning can be adopted.
(1) Thin out back-growing branches and overly dense fruiting branch groups, so that the inner canopy has ventilation and light, and cultivate more small branches in the inner canopy. For temporary branches that have already fruited, weak branches, drooping branches and overly dense outer branches should also be thinned. For elongated branches that grow out, also keep 2-3 branches according to direction. Thin out the rest. In short, open the inner canopy for ventilation and light, which is beneficial to photosynthesis, nutrient accumulation, and flower bud formation.
(2) Flexible application of heading back and pinching: for branches that have fruited and let in light, carry out heading back to promote sprouting below, so that next year's fruiting position does not move outward. For the inner-canopy branches retained in the above thinning, pinch them, leaving about 10 cm, and continue to grow branches, continue pinching, so that they form flower buds and become small fruiting branch groups in the inner canopy. For outer branches, you can leave them longer and pinch at 25 cm-30 cm. With large space, expand the range of growth and fruiting.
For controlling the growth of excessively vigorous large cherry trees, spray the fruit tree growth control agent PBO from June to July, strictly according to the instructions.
3. Timely control of pests and diseases: at present in Shaanxi, cherry diseases include gummosis, shot-hole brown spot disease, and anthracnose. Pests include leafminer, red-necked longhorn beetle, and mulberry scale. During the occurrence period, adopt an integrated method of controlling pests and diseases together. You can choose 25% Jinlishi 6000-7500 times + Ainuo Chongqing 8000 times, or Anminle, Guolong, Baogui, Nanbao, Anmian Te and Abamectin-chlorpyrifos. For fungicides, you can also choose Jianlitong, Pudejin, Namixin, etc. Control the usage amount according to the instructions. No matter which pesticide is used, first use Roushuitong 4000 times to make the mixing water neutral, then mix the pesticide according to the proportion. At the same time as mixing, add Guoyou amino acid or Shuofeng 481 foliar fertilizer 6000 times liquid.
From June to July, attention should also be paid to irrigation and drainage during waterlogging. The ecological requirement of cherries is that they fear both drought and waterlogging. Achieving spring irrigation and summer drainage is the key technology for large cherry water management.