What to Do About Poor Apple Coloration? Causes and Solutions
Apple is the most widely grown fruit in the world, and our country is also an apple producing and exporting country, with cultivation in every region. During the fruit ripening stage, apples go through a coloring period. The quality of the coloration is tied to the quality of the apple; poor coloration leads to reduced quality and can affect the grower's income. So what causes poor apple coloration? How should it be solved? Let's take a look.
1. Poor variety
After many years of cultivation, apples come in a great many varieties, and varieties introduced early on have begun to age, leading to poor coloration, such as Changfu No. 2. In this situation, choose varieties bred later, such as the Yanfu series and Red General, which color better.
2. Insufficient light and water
Light and water are important factors before apples color. If the orchard is densely planted and closed in, with poor ventilation, the fruit cannot get enough sunlight and will not color; in addition, during the apple coloring period, if it is dry with no rain, apple coloration will also be poor.
For insufficient light and water, strengthen orchard management, prune the trees promptly, improve ventilation and light penetration between the trees so the fruit gets enough sunlight to color, and water promptly in drought to keep the soil moist, while also increasing humidity in the orchard to promote fruit coloration.
3. Unbalanced nutrition
Unbalanced nutrition is also an important cause of poor apple coloration. In an environment with too much nitrogen and too little potassium, apples will color poorly, while a lack of magnesium will cause them to lose their green color. The main reason for this phenomenon is that growers fertilize blindly, without achieving a balanced nutritional mix, applying inorganic fertilizer or chemical fertilizer over the long term while applying little organic fertilizer, favoring nitrogen fertilizer over phosphate and potassium fertilizer, or not applying potassium fertilizer at all. This leaves the soil elements unbalanced and unable to supply the various elements the plants need for growth, thus affecting yield and quality.
In this case, change the fertilization method, pay attention to applying organic fertilizer, base fertilization mainly on organic fertilizer with inorganic or chemical fertilizer as a supplement, apply as little chemical fertilizer as possible, and also pay attention to the balance of nitrogen, phosphate and potassium fertilizer. Especially during the coloring period, pay attention to the use of potassium and magnesium fertilizer to meet what the fruit needs for normal coloration.
4. Improper pruning
Apples are generally pruned in summer and autumn, mainly to remove upright vigorous shoots, water sprouts, overly dense branches, crossing branches and overlapping branches, to improve ventilation and light penetration in the orchard, promote photosynthesis, accumulate more nutrients, and at the same time reduce unnecessary nutrient consumption so the trees grow better. But if pruning is done too late or is excessive, it has the opposite effect and affects normal apple coloration.
Pruning should be based on the growth status of the trees and conditions in the orchard, and should be done appropriately, and the timing must also be controlled well; at the latest, it should be done before bag removal.
5. Poor quality of fruit bags
Poor quality fruit bags also affect apple coloration. Choosing inferior bags, which block light poorly and do not withstand rain washing, means they are easily damaged and torn and do not serve the purpose of bagging. Bagging is meant to inhibit the formation of chlorophyll and promote anthocyanin synthesis, and improper timing of bagging and bag removal also leads to poor coloration.
When choosing bags, buy from reputable manufacturers and select high-quality double-layer paper bags with good shading and resistance to rain washing. Bagging should be done after the young fruit is 30 days old, and bag removal should be 1-2 weeks before harvest. Observe carefully before harvest: varieties that color well should have bags removed a little earlier, while varieties that color poorly should have bags removed a little later.
The above are the causes of poor apple coloration and the solutions. We hope it helps you. To learn more about apple growing, please stay tuned to us.