Fruit tree application base fertilizer(humic acid fertilizer):
Generally after the fruit tree leaves fallen in winter, choose the organic matter content is more than 80%. The humic acid content is more than 40% humic acid organic fertilizer. 250-300KGS per MU. Or the organic matter content is 30 %. The humic acid content is more than 20%. The nitrogen, phosphorus and potassium content is about 20%. The organic-inorganic compound fertilizer with high humic acid content , 300-400 kg / mu.
Humic acid organic-inorganic compound fertilizer has sufficient nutrients and comprehensive nutrition. Which can meet the nutrients needed for the growth and germination of fruit trees. The fertilizing position was at the edge of the crown projection. And the trench was dug at the edge of the crown projection. Then fertilized by trench application or hole application. Because the bottom of the crown is also the densest place of root distribution. Fertilizing on the edge of the crown will not hurt the root system. But also conducive to the absorption of fertilizer.The big crown, the aged tree dug two times, the depth of 20 -40 cm. Fertilizer can not be buried too shallow. Or it is not conducive to root absorption. After fertilizing and burying, it should be fully watered to facilitate the absorption of fruit trees.
Fruit tree topdressing
When the fruit tree grows to the fruit expansion stage. Select the humic acid organic-inorganic compound fertilizer with nitrogen, phosphorus and potassium content of about 25-30%, 80-160 kg / mu. Or select 30% nitrogen, phosphorus and potassium humic acid compound fertilizer to irrigate the root along the ditch. So that the fruit tree absorbs well and the effect is fast.
Fruit trees need to be fertilized four times a year.
The first topdressing should be pre-flowering fertilizer.
The germination and flowering of fruit trees consumes a lot of nutrients. And if the nutrients are not available, it will lead to the prolongation of flowering and the decrease of fruit setting rate. So it is necessary to apply available fertilizers in proper amount.
The second time is the flower after fertilizer.
The top dressing is to be carried out immediately after the flower is dropped. So as to reduce the physiological fruit drop, promote the growth of the new shoot and enlarge the leaves. The first and the second top dressing should be closely combined to apply quick-acting nitrogen fertilizer. And each aged tree is 100 kg manure or 1 kg of potassium humate.
The third time topdressing at the stage of fruit expansion and flower bud differentiation.
At this time, the fruit is rapidly expanded. The flower buds begin to differentiate. The reproductive growth and the vegetative growth are sharp. And a proper amount of nitrogen, phosphorus and potassium fertilizer can be applied in time. So that the photosynthetic effect of the leaves can be improved. The nutrient accumulation is promoted. And the requirements of fruit expansion and flower bud differentiation on nutrition can be met.
The fourth time topdressing is when stop growing after autumn shoots.
The main function is to improve the photosynthetic function of the leaves. Increase the accumulation of the nutrients in the tree body. And promote the differentiation and full of the flower buds.
For the third and fourth topdressing. 50 kg of manure, 1 kg of potassium humate and 0.5 kg of fulvic acid were applied to adult trees. The fourth fertilizing time: early maturing, medium maturing varieties can be carried out after harvest. late maturing varieties should be carried out before harvest.
Except for regular fertilizer, 250 times borax aqueous solution was sprayed at flowering stage. 200 times urea or potassium humate extract or potassium fulvate solution were sprayed at fruit expansion stage. And the effect was very good. Irrigation should be carried out in time after each fertilizer.