A Complete Guide to Fertilization Techniques and Key Points for Chestnut Orchards
Chestnut blight, also known as chestnut canker, trunk blight, or chestnut bark disease, is a major disease of chestnut trees. It mainly affects the trunk and main branches, often causing the trunk and main branches to rot until the entire tree dies. The chestnut blight pathogen mainly overwinters in diseased branches as mycelium, pycnidia, and perithecia, while conidia and ascosp...
I. Apply sufficient basal fertilizerBasal fertilizer is the fundamental fertilizer supplying the chestnut tree's growth and development throughout the year. It can enhance the photosynthetic efficiency of leaves, help restore tree vigor, accumulate more nutrients, and lay the foundation for a high yield the following year. Generally, after fruit harvest in autumn, it is applied together with deep plowing to improve the soil, mainly using organic fertilizer. For trees of moderate vigor, with medium fertility and a relatively heavy fruit load, apply about 2000 kg of decomposed farmyard manure per mu, and 1.0-1.5 kg of sulfur-based compound fertilizer per tree.
The main fertilization methods are: ① Radial trench application. With the trunk as the center, dig 4-6 radial trenches at equal distances along the edge of the canopy. The trenches are 30-40 cm wide, and the length depends on the size of the canopy; generally half the trench length is inside the canopy and half is outside the canopy. The trench depth is about 30 cm, and the depth should gradually increase from the inside outward. ② Ring trench application. Dig a ring-shaped trench 40-50 cm wide and 50 cm deep 20-30 cm outside the canopy, and apply fertilizer into it. This method is suitable for young trees with smaller canopies. ③ Strip trench application. Dig fertilization trenches 50 cm deep and 40 cm wide on opposite sides slightly outside the canopy, with the length depending on the size of the canopy, and apply fertilizer into them.
II. Reasonable supplementary fertilization
Pre-flowering fertilizer: Generally, the first application is before and after budbreak, mainly nitrogen fertilizer, and 0.3-0.5 kg of high-nitrogen compound fertilizer per tree can be applied. It can promote leaf growth and shoot development, flowering and fruiting, and increase the fruit-setting rate and yield.
Fruit-swelling fertilizer: Apply it after flowering during the early stage of fruit enlargement, with 0.5-1 kg of high-potassium compound fertilizer per tree. It can promote fruit enlargement, increase yield and improve fruit quality.
In addition, from May to July during the growing season, when spraying pesticides for pest and disease control, manganese and magnesium elements should be added for mixed spraying to supplement micronutrients. This extends the functional period of leaves, increases the single-nut weight, and boosts the accumulation of nutrients in the fruit, thereby improving the commercial value of the fruit.