recently, many fruit farmers have a question, citrus has reached the expansion stage, why not grow long. is it because the water and fat can't keep up? in fact, there are many reasons why the citrus doesn't grow. let's analyze the situation of slow fruit expansion and short growth of oranges and how to promote the growth of oranges!
the period of fruit expansion has come. why don't oranges grow long?
① still in the stage of physiological fruit falling
according to the past experience, the second physiological fruit drop of citrus usually ends at the end of june and then enters the stable fruit period, but in recent years, the abnormal climate conditions and the change of cultivation technology make the second fruit drop generally extend, some even more than a month. just think, if even the fruit is not stable, how can it expand?
(2) the deficiency of expanding fruit elements
when it comes to fruit expansion, many people only think of potassium fertilizer. in fact, when citrus fruit expands, it needs nitrogen, phosphorus, calcium, magnesium and other trace elements. of course, it also includes carbon, hydrogen and oxygen.
for example, carbon is the basic component of organic matter in plants; hydrogen and oxygen are water, and the fruit expanding stage of citrus is also called water filling stage; the demand of nitrogen in fruit expanding stage is similar to that of potassium; phosphorus can promote cell division; magnesium can improve photosynthetic efficiency, etc.
③ uneven distribution of nutrition
the nutrient of citrus tree is limited. when there are too many fruits or the contradiction between the top and the fruit is intense, the nutrient distributed by the fruit will decrease, resulting in slow fruit expansion and small fruit.
④ weak tree
the leaves are less yellow and weak, and the organic nutrients accumulated in the tree body are relatively less, which is difficult to supply for fruit expansion and shoot growth, resulting in slow fruit expansion and small fruit.
in the early stage, improper circumcision resulted in root starvation, waterlogging resulted in long-term anoxia of root system, drought caused stress to root growth, improper application of fertilizer caused root burning, and so on.
measures to promote citrus growth:
① guarantee nutrition supply
in this period, in addition to the coordinated application of nitrogen, phosphorus and potassium, we should pay attention to the appropriate supplement of calcium, magnesium and zinc to ensure the normal supply of expanding elements, and reduce the occurrence of cracking, premature aging, sunburn and other problems.
flourishing trees with few fruit: if the fruit expansion is slow, the contradiction between the top and the fruit is serious. at present, it is suggested to control nitrogen and potassium, increase the application of medium and micro fertilizer to regulate the tree vigor, expand the fruit and repair the type, and put off the shoot till about the middle of august.
weak trees with more fruits: in this period, a certain amount of total nutrient fertilizer, such as peanut bran water high potassium water and fertilizer, should be properly applied to help stabilize trees and fruits. this kind of trees should be put in advance. before the summer heat, if they haven't come out at present, they should be sprayed with biological stimulant immediately and pruned to get out as soon as possible.
② root cultivation and leaf protection
root system is the basis of fertilizer and water absorption, and leaves are the workshop of organic nutrients. therefore, fruit expansion period is very important for the maintenance of roots and leaves.
the maintenance of root system is mainly to provide a good soil environment. in this period, water management and control should be done well to prevent waterlogging and drought. at the same time, some water and fertilizer containing humic acid and seaweed extract can be applied to improve the physical and chemical properties of the soil, strengthen the root and promote the root, and enhance its resistance ability.
in this stage, we should prevent mites, leafminer, stink bug, elephant beetle, thrips, canker, anthrax, brown spot and so on, as well as sunburn.
③ reasonable fruit thinning
for trees with excessive fruit bearing capacity, remove the diseased fruits, deformed fruits, cracked fruits and abnormal fruits, cut off the shady branches and diseased branches, enhance the light transmittance of trees, improve photosynthesis, and ensure the effective supply of nutrients.