What are the measures for citrus flower and fruit retention
AbstractFertilization and spraying: Citrus can be sprayed with trace elements and flower-promoting and fruit-retaining agents before flowering. Water management: During the fruit-retention period, the soil should be kept moist, and drainage should be done well during the rainy season. Girdling for fruit retention: In the early stage of physiological fruit drop, a small knife can be used to girdle the trunk or a large branch 1 ring; it is necessary to cut through the phloem, but the xylem must not be damaged. Pruning new shoots and pinching: Prune off excessively vigorous spring shoots, then pinch. Shaking flowers on rainy days: During the flowering period, the citrus tree can be shaken after rain, which helps enhance light exposure.
1. What are the measures for citrus flower and fruit retention
1. Fertilization and spraying
To promote the maturity of spring shoots, enhance plant vigor, promote robust flower bud development, and reduce citrus flower and fruit drop, various types of trace elements can be sprayed before flowering, along with flower-promoting and fruit-retaining agents, which helps improve flower bud quality.
2. Water management
To improve the stress resistance of the fruiting mother branches, the soil should be kept moist during flood prevention, drought prevention, and fruit retention, so as to avoid root rot caused by an imbalance between dryness and moisture, which would cause heavy citrus fruit drop. In particular, irrigation should be done promptly during drought weather, and drainage work should be done well when there is excessive rain.
3. Girdling for fruit retention
For trees with relatively vigorous growth, in the early stage of the 1st physiological fruit drop, a small knife can be used to girdle the trunk or a large branch 1 ring. In the early stage of the 2nd physiological fruit drop, depending on tree vigor and fruit load, another girdling can be done, which helps increase the fruit-setting rate. Girdling needs to cut through the phloem, but the xylem must not be damaged. Old and weak trees are not suitable for girdling.
4. Pruning new shoots and pinching
To resolve the conflict between shoot growth and fruiting, first prune off excessively vigorous spring shoots. For shoot branches, part of the new shoots can be pruned according to the principle of removing 2 out of 3 and removing 3 out of 5, and then pinching should be carried out. When spring shoots grow to 15cm, pinch promptly to save nutrients. Finally, when summer shoots grow to 3-5cm, prune them all off and remove the summer buds, which helps reduce nutrient consumption and reduce plant fruit drop. Continue until early to mid-July, when the 2nd physiological fruit drop ends.
5. Shaking flowers on rainy days and enhancing light exposure
The citrus flowering period happens to coincide with rainy weather in the south. After flowering, the petals will stick together, resulting in poor light exposure, and the petals are prone to turning yellow and falling off. Therefore, the trunk can be shaken after rain, which helps enhance light exposure and promote healthy citrus growth.
2. How to determine the fruit retention amount of citrus trees
1. The fruit retention amount of citrus trees can be determined according to the bearing capacity of the tree body. Simply put, strong trees bear more fruit and weak trees bear less. Strong trees bear more fruit because strong trees have lush branches and leaves, so photosynthesis is strong, and the nutrients produced are also relatively greater, which can provide the nutrients needed for growth to more fruits and helps increase the fruiting rate.
2. This can increase yield, reduce coarse-skinned fruit, slow the expansion of the tree canopy, and reduce branch crossing and closure. Weak trees bear less fruit because weak trees produce relatively fewer nutrients, so the nutrients provided can only meet the needs of a small number of fruits for growth and development. If a citrus tree bears too much fruit, not only will the fruit become smaller, but the tree body will also become weaker, and it may even cause no fruiting.
3. The bearing capacity of the tree body is mainly determined according to indicators such as tree vigor, canopy size, leaf color, and leaf quantity. Generally, the fruit bearing capacity is calculated according to the leaf-to-fruit ratio. For different citrus varieties and types, the number of leaves required to bear 1 fruit is also different.
4. Suitable leaf-to-fruit ratios: mandarin and tangerine 40-60:1, pomelo types 100-200:1, navel orange and other sweet oranges 30-50:1, extra-early and early-maturing Satsuma mandarin 23-35:1, mid-late maturing Satsuma mandarin 20-25:1, small-leaf loose-skin mandarin 50-60:1.