In the spring, which is a critical period for citrus growth, the tree body has absconded from hibernation and has begun to draw, long leaves and flowers, and the demand for nutrients has increased significantly. After winter consumption, nutrient reserves in the soil are limited, and citrus trees may grow slowly without timely resupply of spring fertilizers, affecting subsequent yields and quality. However, the application of spring fertilisation is not casual, and two basic conditions must be met: the soil must be sufficiently moist, and no good fertilisation can be absorbed without water; temperatures must exceed 12 degrees, because below 12 degrees is less active, is less fertilizing, and fertilization can be significantly reduced。
At the heart of the application of spring fertilisation is rooting, with its first growth peak, using hormonal-free root agents or microbial polymeric biocofertilizers, which can contribute rapidly to the growth of the root system, improve the structure of soil pellets and microbacteria, improve the capacity of trees to absorb nutrients and lay the foundation for year-round management. The selection of fertilizers is based on the priority of water solubility of a large number of fast-acting elements, such as the herring system, olympics and sugar oranges, the need for high-yield supplementation in spring products, the poor velocity of conventional composite fertilizers or potassium sulphate-based fertilizers, the long transformation cycle and slow absorption, which can affect tree recovery and flowering. The low use and burden of quick-impact water soluble fertilizer, which is stable, enables the rapid restoration of tree positions, promotes flowering and increases sit-in rates, and is well recognized by growers。
The foliage cannot be ignored, as most citrus varieties in the spring are in a budding phase, with a high demand for moderate micronutrients, when a single element of boron and polymeric amino acid-based foliage is sprayed, quickly replenishes the nutrients required for the ferns to divide, improves the quality of the buds, and opens the ostrich of the leaves and promotes light cooperation. In orchards with fat leaves, the buds are split quickly, the flowers are full, and the post-sitting rate is higher。
The timing of fertilization is adjusted to the direction of the tree, where the strong tree is sprouts at the end of march, allowing for timely supplementary nutrition and growth; and the strong tree is applied in april to avoid excessive nutrient growth. Fertilizer formulations also differ from one region to another, with potassium formulations (20-13-12) from high nitrogen phosphorus used in the mid-range citrus belt in the yangtze, yielding 14-18 kg per acre under 1,000 kg and 18-30 kg per acre under 1000 kg per acre, to 22-11-12 kg per accelerator under 10-15 kg under 1000 kg and to 15-25 kg for 1000-2000 kg per acre under 1000 kg。
Micronutrients are required to be “composed due to deficiency” and mangroves are designed to replenish magnesium, calcium, boron, zinc, iron and boron, with 1 - 1. 5 kg of zinc sulphate per acre prior to sprouts, 0. 5 - 1 kg of bolint, 2 - 3 times during the berries at the beginning of flowering; 20 - 30 kg of magnesium sulphate in the larvae and 2 - 3 times of calcium spray。
In addition to fertilizing, there is also a combination of management, with plastic cutting before fertilisation in the spring, cutting of late-cooked varieties, planning of tree trunks and new positions; timely cutting of dead branches by frozen trees and the application of high-quality organic fattening to the root system after the temperature rises; and conditional water fertilizer integration techniques to increase fertilizer utilization. It is only through a combination of fertilizer and management that rich trees and high-quality fruits can be grown。
