What fertilizer should be added to alpine chestnut trees in winter?

Do a good job in planting because the soil fertility in mountainous areas is poor. Before planting, improve the soil, change the soil and apply sufficient fertilizer.

The chestnut orchards in mountainous areas should be scientifically fertilized with organic fertilizer, with a reasonable combination of nitrogen, phosphorus and potassium (65,438+0: 65,438+0.5: 65,438+0.5). It is suitable to apply organic fertilizer in autumn, with a dosage of 4,000-5,000 kg per mu. In addition, topdressing boron fertilizer can greatly reduce the rate of empty bracts and improve the yield. Borax 10 ~ 20g should be applied to each square meter of crown projection area.