Detailed Explanation of Chestnut Planting Techniques and Management Methods
Chestnuts are quite familiar to everyone, because we eat chestnuts for a period every autumn and winter. Chestnuts have particularly wide uses and very high nutritional value, and growing chestnuts has broad prospects. So how should chestnuts be scientifically planted? Below, let us learn the technical knowledge of chestnut planting together!
Chestnut Planting Techniques
1. Site selection. Chestnut trees should be planted on soil with deep soil layers, relatively fertile, neutral or slightly acidic, and good drainage. In mountainous areas, the planting altitude generally should not exceed 400 m. It is best to plant on sunny slopes; otherwise there will be fewer burs and a high rate of empty burs.
2. Land preparation and fertilization. For planting in plots on flat land or gentle slopes, the land should be fully dug and turned (gentle slopes made into level terraces), then pits 0.8-1 m long and wide and 0.5-0.6 m deep should be dug. Apply 50-100 kg of decomposed organic fertilizer, 0.5-0.6 kg of urea, and 0.4 kg of superphosphate per pit, mix thoroughly, and apply into the pit. For soil that is more acidic, also apply a small amount of lime. Some soils have available boron content lower than 0.5 ppm, so 10-15 g of boron fertilizer should also be applied per hole as base fertilizer to prevent large numbers of empty burs caused by boron deficiency in chestnut trees, which leads to reduced yield.
3. Planting. Generally, flat land is planted with 40-50 plants per mu in a square arrangement. Sloping land is planted with 60-70 plants per mu in a rectangular arrangement. After the trees mature, thinning can be carried out, or pruning can be used to force the canopy to develop upward, so as to build a fast-growing dense plantation favorable for early high yield. Before the plantation is established, cash crops can be intercropped, using cultivation instead of tending. The suitable planting time is November-December and mid-February to early April. When digging up seedlings, try to avoid damaging the root system. When transporting seedlings over long distances, dip the roots in mud and wrap them with rice straw. After lifting the seedlings, plant them early; those that cannot be planted immediately should be heeled in first. The seedlings must not be planted too deep; the healed part of grafted seedlings should be exposed above the ground to prevent rotting.
4. Planting pollinizer trees. The self-pollination rate of chestnuts is relatively low, so when selecting and planting the main chestnut varieties that are suitable for local conditions and have excellent quality and high yield, another variety whose flowering period is slightly later must be uniformly mixed in at 10%-15% to facilitate cross-pollination and ensure a bumper harvest.
Chestnut Cultivation Techniques
1. Seedling propagation. Chestnut propagation methods mainly include seedling propagation and graft propagation. Although seedling propagation is simple, has lower cost, and produces long-lived plants, it cannot maintain the excellent traits of the variety, and there are large differences among individual plants; generally it bears late and has low yield. Therefore, in recent years, graft propagation has mostly been used for chestnut development in various places.
2. Selection of chestnut seed. There are two uses for sowing and raising seedlings: one is as rootstock, and the other is directly for production planting. Seedlings used as rootstock are required to grow robustly, so fully mature nuts that are uniform in size and free of pests, diseases, and mechanical damage should be selected as seed. Seed used for seedlings directly for production planting must be collected from mother trees that grow robustly and are high-yielding and high-quality, so as to ensure good performance of the offspring.
3. Sowing. Chestnut sowing can be divided into autumn sowing and spring sowing. Autumn sowing is mostly done in late autumn and early winter. The advantage of autumn sowing is that the chestnuts do not need sand storage and can be sown after slight treatment following seed collection. However, because the chestnuts remain in the field for a longer time in autumn sowing, they are susceptible to external climate and other damage, affecting the emergence rate. Spring sowing requires about 30% or more of the seed to have sprouted, or is carried out in early to mid-March each year.
4. Seedling management. After the seedlings emerge, cultivate and weed immediately, which is especially important for direct-sown plantation establishment, to ensure seedling growth. One month after seedling growth, the nutrients in the seed have been exhausted, so fertilizer can be applied twice in early June and early August, about 5-10 kg of urea per 666.7 sq m, and irrigation should be carried out immediately after application. Chestnut seedlings are afraid of waterlogging; after fertilization, besides irrigation when the soil lacks water, drainage should be carried out in time during the rainy season to avoid prolonged water accumulation in the nursery. Pests and diseases should also be controlled in time to ensure complete and robust seedlings.
5. Fertilization. The growth cycle of chestnuts is divided into the bud break stage, new shoot growth stage, flowering stage, and fruit development stage. Fertilization is divided into base fertilizer and topdressing.
Chestnut Varieties
China has a vast territory and greatly differing ecological conditions, forming a great many chestnut variety resources. No fewer than more than 300 chestnut varieties in the country have been named, but they can generally be divided into two major variety types, namely northern chestnuts and southern chestnuts.
1. Northern chestnuts
They are mainly distributed in the Yanshan and Taihang Mountain areas of North China and nearby areas. This includes Hebei, Beijing, northern Henan, Shandong, parts of Shaanxi and Gansu, and northern Jiangsu. Their characteristics are small fruit shape, with an average single nut weight of about 10 g; glutinous flesh, with sugar content as high as about 20%; low starch content in the flesh and high protein content; relatively dark and glossy nut skin; strong aroma, and the astringent skin is easy to peel off; suitable for roasting, known as sugar-roasted chestnuts.
2. Southern chestnuts
They are mainly distributed in Jiangsu, Zhejiang, Anhui, Hubei, Hunan, and southern Henan. In this region, with high temperature and abundant rain, chestnut nuts are large, with an average single nut weight of about 15 g and a maximum of up to 25 g, but with low sugar content and relatively high starch content, and the flesh tends to be non-glutinous, so they are mostly used as vegetable chestnuts. There are many chestnut varieties in northern and southern China, and there are differences in the characteristics and traits of the southern and northern variety groups. Generally, the quality of the southern variety group is not as good as that of the northern varieties, and the flesh tends to be non-glutinous, suitable for stir-frying, also called vegetable chestnuts.
What Is the Yield of Planted Chestnuts
The yield of chestnuts is related to the age of the chestnut trees, fertilization and management level, and different planting areas. Generally, 1-2 year old chestnut seedlings are grafted in the same year after planting and can bear fruit the next year. After grafting, the average yield from 2-4 years is about 2674.5 kg per hectare (178.3 kg/mu), from 3-7 years is about 4650 kg (310 kg/mu), and after the 7th year is about 6405 kg (427 kg/mu).
After chestnut trees grow for eight years, canopy closure is difficult to control, and transplanting is required. Otherwise, with high density and poor light penetration, only the top bears fruit and the surrounding parts do not, causing serious yield reduction in chestnuts. Therefore, old chestnut trees should be transformed into an open-center shape to increase yield. For old-style trees, leave more than 12 branch tips per sq m; for pruning to reduce flowers and control the canopy, leave 5-6 branches per sq m. The highest chestnut yield per sq m does not exceed 1 jin, which is 667 jin per mu; with good management, yield per mu can reach 500 jin to 600 jin.
As described above, if you want to increase chestnut yield, understanding chestnut cultivation techniques is key, and attention should be paid to site selection, seedling selection, and planting. Although chestnut trees are easy to cultivate, in fact both the early and later stages require good care. With good care of chestnut trees, the chestnut yield the following year can show you a surprise!