What fertilizer can increase the sweetness of citrus fruits? (Citrus fruits will be very sweet if foliar fertilizer is applied)

The sweetness of citrus is the most important factor in its quality. However, many people know that to make citrus fruits sweeter, they do not know that it is more important to reduce the acidity, because only when the acidity is reduced can the sweetness of citrus be highlighted.

Sweetness composition of citrus

The sugars in citrus fruits are mainly sucrose, glucose and fructose. Among them, fructose has the highest sweetness and glucose has a better taste. Only by increasing the content of these sugars in a balanced way can we have citrus fruits with excellent taste.

Generally, in the early growth of citrus fruits, sugar is mainly deposited in the flesh cells, and gradually increases in the middle stage, reaching a peak at maturity. Therefore, the late stage of citrus fruit expansion is the key point for sugar increase.

Where does the sour taste of citrus come from?

In addition to sugar, citrus fruits also have a sour taste. This is because they contain two amino acids, citric acid and malic acid.

Among them, citric acid produces sour feeling quickly and lasts for a short time; malic acid tastes refreshing and slightly bitter, develops taste slowly, and maintains the sour feeling for a long time.

During the growth of citrus fruit, organic acids will continue to accumulate and will gradually decrease when the organic acid level reaches its peak.

We all know that delicious citrus fruits must be sour and sweet, so we must grasp the sugar-acid ratio of citrus fruits.

When the sour content of citrus is 1%, the sugar content must be more than 10% to have a good taste, that is, the sugar-acid ratio must be greater than 8.2. When the sugar-acid ratio is greater than 12, the taste of citrus will be sweet.

What factors affect the sweetness of citrus?

① Environmental factors

Citrus requires suitable temperature and light to grow. When the temperature rises, the sugar content and soluble solids will continue to increase, and the acidity will decrease accordingly.

Insufficient light will hinder photosynthesis, affect sugar accumulation, reduce sugar content, increase acid content, and reduce quality.

②Water factor

Water is a necessary factor for the growth of citrus. On the premise of meeting the basic water supply, the amount of watering for citrus can be reduced within a certain period of time. This can increase the soluble solids and sugar content in the fruit juice.

③ Fertilizer factors

Minerals can further reduce acidity and increase sweetness. For example, magnesium, zinc, calcium, potassium, etc. will reduce the assimilation products of fruit trees by affecting their photosynthesis.

The lack of iron and calcium will affect the degradation of organic acids; phosphorus deficiency will cause the fruit to become smaller, hollow, have rough and wrinkled skin, be lighter in color, contain less juice, and have a stronger sour taste.

In the later stage of citrus growth, it is necessary to ensure the supply of phosphorus and potassium fertilizers so that the citrus can have a good taste.

What fertilizers are used to sweeten citrus fruits?

① Apply basal fertilizer in winter

If you apply base fertilizer mainly composed of organic fertilizer in the autumn after picking, the early base fertilizer is easy to ferment and decompose and easily absorbed by the tree, which is conducive to the decomposition and transformation of organic fertilizer in winter and spring and the continuous release of nutrients.

This will allow the citrus to grow new roots in time, which will help it to quickly resume growth and vitality next year. By supplying the nutrients needed for flower bud differentiation and early flowering and fruiting of citrus trees, it promotes flower bud differentiation, prevents flowers and fruits from falling, and can significantly increase the yield and quality of citrus fruits.

② Increase the application of calcium fertilizer

According to research, the acidity of citrus fruits is related to the calcium content in the soil. The higher the calcium content, the lower the acidity of citrus fruits, and vice versa. There is a general lack of calcium in the soil.

Therefore, adding calcium fertilizers such as lime to the soil in citrus orchards can effectively supplement the calcium content in the soil and at the same time supplement the calcium nutrients needed during the growth period of citrus.

Generally, 50-60 kg of quicklime per mu is spread on the soil of the orange orchard to reduce the acidity of the soil, increase the accumulation of sugar and increase the sweetness .

③Spray foliar fertilizer

Under normal circumstances, if mineral nutrients are sufficient, many fruit farmers will spray potassium dihydrogen phosphate such as phosphorus and potassium source pools during the citrus ripening period, and the effect is good, with continuous spraying 2-3 times .

Generally speaking, it is not recommended to use foliar fertilizers containing growth regulators such as ethephon to promote early maturity. If conditions permit, you can use it. This foliar fertilizer is registered with elements such as phosphorus, potassium, boron, and molybdenum, and is specifically used to promote color change and sweetness of citrus fruits.