The Latest Methods to Prevent Alternate Bearing in Longan

Longan is widely cultivated in warm regions such as Fujian. Will growing longan bring all kinds of problems? These problems all affect growth and yield. Today we will mainly discuss what to do about alternate bearing in longan and how to maintain balanced and stable yields. A brief introduction for everyone's reference.

I. Causes

1.There are many longan cultivars. Some cultivars have a strong ability to retain flowers and fruit, while others are prone to flower and fruit drop. When choosing, you can select better cultivars.

2.Fruiting mother branches are damaged by borers during the young leaf stage of autumn shoots, resulting in poor growth and the inability to flower and fruit well. Or downy mildew during the flowering period causes heavy flower drop and low fruit set. Drought during autumn shoot emergence and the fruiting period affects bud sprouting, shoot emergence and causes fruit drop. Rain during the flowering period leads to heavy flower drop and failure of pollination and fertilization. A warm winter prevents flower bud differentiation.

3.Blindly pursuing more fruit in years with abundant flowering, without thinning flowers and fruit, excessively consuming nutrients without replenishing them adequately. This causes growth imbalance, no new bud sprouting and no shoot emergence. Extensive management, with no care or attention.

II. Preventive Measures

1.After harvest every winter, you should apply enough farmyard manure along with intertillage to keep the soil fertile and well structured. Weak trees should be supported individually. Dig ditches and channels in the field to do a good job of drainage and irrigation, preventing waterlogging and drought. During the growing period, mainly prevent downy mildew and fruit borer. Prune off damaged and diseased branches, and use efficient pesticides with low phytotoxicity for control to manage pests and diseases.

2.If the canopy is too large, exceeding about 5 m, nutrient transport is too distant and not in place. It is best to cut back and prune the canopy to maintain it at around 3 m so that nutrient transport is timely. In vigorous growing years, be sure to thin out some inflorescences and excess fruit, diseased fruit and weak fruit. This prevents consumption that would otherwise result in failure to produce good fruit. In light fruiting years, pay attention to removing some buds to avoid shoot emergence and concentrate nutrients. During the flowering period, manual pollination can be done to increase fruit set. In addition, apply fertilizer several more times, and be careful to maintain all the nutrients needed during the flowering and fruiting periods. Spray zinc sulfate as a foliar fertilizer to balance the relationship between vegetative growth and reproductive growth.

Grasp the phenomenon of alternate bearing in longan, then compare it with the causes and implement good preventive measures. However, there are many factors that affect the occurrence of alternate bearing. You can combine them with actual conditions to discover the causes yourself and implement your own preventive measures.