A Detailed Guide to the Cultivation Techniques and Growing Methods of the Chinese Medicinal Herb Atractylodes macrocephala
Cultivation Techniques 1. Raising Seedlings (1) Preparing the Seedbed One month before sowing Atractylodes macrocephala, turn the soil, cover it with a 30 cm thick layer of weeds, and burn the soil to disinfect it and prevent pests and diseases. Immediately after burning, turn the grass ash into the soil. If the soil is not to be burned, it can be turned in the previous winter so that the soil is fully weathered by freezing. The land...
Cultivation Techniques
1. Raising Seedlings
(1) Preparing the Seedbed
One month before sowing Atractylodes macrocephala, turn the soil, cover it with a 30 cm thick layer of weeds, and burn the soil to disinfect it and prevent pests and diseases. Immediately after burning, turn the grass ash into the soil. If the soil is not to be burned, it can be turned in the previous winter so that the soil is fully weathered by freezing. After the land has been treated, make beds 100-130 cm wide and about the corresponding height, with the bed surface arched, high in the middle and low around the edges, and apply 150-225 loads of human and animal manure per hectare as base fertilizer.
(2) Sowing
Sow from late March to early April. In arid areas, it is advisable to first soak the seeds in warm water for 24 hours, then take them out and mix them with sandy soil before sowing in the field. Where irrigation is available, the seeds need not be soaked. There are two sowing methods: broadcast sowing and drill sowing. For broadcast sowing, use 150-112.5 kg of seed per hectare; the seed from each hectare can plant 300-450 kg of rhizome planting stock, and generally each 0.5 kg of planting stock contains about 140-150 pieces. For drill sowing, use 60-75 kg per hectare, with a row spacing of 16 cm and a sowing width of 6-10 cm, opening shallow furrows about 3-5 cm deep. The bottom of the furrow should be level so that seedlings emerge evenly. For covering soil, 3 cm of soil can be used; 1 hectare of seedling-raising field can supply 150 hectares of land. Before emergence, the soil should be kept sufficiently moist, or the surface can be covered with wormwood grass or barnyard manure to avoid soil crusting (in Beijing, generally 2-3 waterings are needed for emergence). The latter method is commonly used and is easy to manage.
(3) Seedling Stage Management
After the seedlings emerge, thin out the densely growing seedlings and the diseased and weak ones, and weed in time. When the seedlings are 3-6 cm tall, hoe shallowly. The purpose of weeding is to allow watering during dry weather or to insert branches or spread grass between the rows to achieve shading. When the seedlings are 5-6 cm tall, thin to a plant spacing of 6-10 cm. Depending on the condition of the seedlings, apply topdressing 1-2 times during the seedling stage, using 2250 kg of human and animal manure per hectare diluted with 3 times its volume of water; thin manure or urea is preferable.
The amount used should not be too much. From late July to late September is the root formation period, so more topdressing is applied.
From late October to early November (after Frost's Descent and before the Start of Winter), when the leaves of the Atractylodes seedlings turn yellow, begin digging up the planting stock. Choose a sunny day, remove the stems, leaves and fibrous roots, and cut off the branches and leaves 1 cm from the top. Be careful not to damage the main bud or the epidermis of the rhizome. Dry in the shade for 2-3 days until the epidermis turns white and the moisture content is reduced, then store.
(4) Storage Methods for Planting Stock
Choose a dry, shady place, avoiding direct sunlight. Build a square frame with bricks, first spread a 3-5 cm thick layer of sand, then a 9-12 cm thick layer of planting stock, then another layer of sand, stacking up to 30 cm high, and insert several bundles of rice straw in the center of the pile to improve ventilation. Cover the top with a layer of sand or soil; at first it should not be too thick, to prevent heating and rotting. During severe winter cold, add another layer of rice straw. The sand and soil should be moderately dry and moist; if the sand is too dry it will absorb water from the planting stock, and if too wet it will cause the planting stock to sprout early. During storage of the planting stock, inspect once every 15-30 days, and promptly remove any diseased stock to avoid causing rot. If the planting stock begins to sprout, turn it over to prevent the buds from growing. For small quantities, store in jars or pots, cover the mouth of the jar with sand or cover with green pine leaves, and replace the pine leaves as soon as they dry; inspect frequently and immediately peel off and remove any that rot. Pit storage: choose a shady spot and dig a pit 100 cm deep, with the length depending on the amount of planting stock. Place the stock in the pit in a 15 cm thick layer, cover with 5 cm of soil, and add more as the temperature drops, covering 30-50 cm during the coldest weather; inspect once every 10-20 days. Another method is open-air storage, that is, the Atractylodes planting stock is not dug up but left in the field to overwinter.
(5) Selecting Planting Stock
This can be done either after harvest or before planting, but it is best to sort the planting stock after harvest while grading it by quality into large, medium and small, and remove all diseased ones. Selection criteria: uniform shape, free of pests and diseases, plump buds, upper part of the rhizome slender and lower part round, and as large as a frog in shape, with densely growing soft fibrous roots, and the main root short and slender or absent; planting stock grown in high-mountain virgin soil is considered of superior quality. Any planting stock that is deformed, whose top is a lignified stem, whose fibrous roots are thick, hard and sparse, whose main root is thick and long, or that was grown in low-mountain cultivated land is of inferior quality, grows poorly after planting, and is susceptible to disease, so it should not be selected.
2. Land Preparation and Planting
Planting can be done from late December to late March of the following year (from the Winter Solstice to the Spring Equinox of the next year). Generally, it may be advanced or delayed according to soil and climatic conditions. Early planting usually results in roots growing first and then sprouting, with a deep root system, robust development, and strong drought resistance and nutrient uptake. In areas with shallow soil and poor heat retention, planting can be delayed to February or March. Plant at a depth of about 5-6 cm; shallow planting easily produces lateral buds, making the rhizome shape unattractive, and in cold places it is prone to frost damage; planting too deep makes sprouting difficult and produces a slender rhizome, lowering quality.
Planting methods can be divided into drill planting and hole planting. The former uses beds 200 cm wide, and the latter uses beds 130 cm wide, with row and plant spacings such as 26 cm * 13 cm and 20 cm * 13 cm. The planting density is 15000-180000 plants per hectare, and the amount of planting stock is about 750 kg per hectare.
3. Field Management
(1) Cultivation and Weeding
Loosen the soil shallowly; in principle, keep the field free of weeds. Loosen the soil shallowly before the seedlings emerge, and weed when the seedlings are 3-6 cm tall. Do not let the soil crust. Do not weed after rain while the dew has not yet dried, otherwise it is easy to contract leaf spot disease. From late July to late September, which is exactly the time of root growth, pull weeds 1-2 times a month.
(2) Topdressing
Apply sufficient base fertilizer, mainly rotted barnyard manure or compost. Per hectare, use 11250 kg of human and animal manure and 375-525 kg of superphosphate as base fertilizer. In early May, when the seedlings have basically all emerged, apply one application of thin human and animal manure at 7500 kg per hectare. Around the fruiting period is when Atractylodes macrocephala has the strongest nutrient uptake, the fastest growth and development, and the most rapid enlargement of the underground rhizome during its entire growth period. Generally, at full bloom, apply 15000 kg of human and animal manure and 450 kg of superphosphate per hectare.
Method: Open small holes between plants, apply, then cover with soil; do this after the morning dew has dried.
(3) Irrigation and Drainage
Atractylodes macrocephala dislikes high temperature and excessive moisture, so attention must be paid to drainage. If drainage is poor, it will hinder the growth of the plants and make them prone to disease. Standing water in the field can easily kill the seedlings, so pay attention to digging ditches, clearing ditches, and draining promptly after rain. In late August the rhizome enlarges noticeably and needs a certain amount of water. If there is a long drought, water appropriately to keep the field moist; otherwise yield will be affected.
(4) Special Management
(1) Removing Flower Buds
In order to concentrate nutrients to supply the rhizome and promote its growth, except for seed plants, for which 5-6 flower buds per plant are retained, all the rest must be removed at the right time. This is generally done from mid-July to early August, that is, completed in 2-3 rounds within 20-25 days. Remove the flowers when the small florets have spread open and the scales wrapping the outside of the bud are slightly yellow. It should not be done too early or too late; removing buds too early, when the plants are still tender, will cause poor growth, while too late will consume too many nutrients. The standard is that the stem of the flower bud is relatively brittle and easy to snap off. Hold the stem with one hand and pick the flower with the other, keeping as many small leaves as possible and preventing the base of the plant from being shaken; scissors may also be used to cut them off. Remove buds on sunny days after the morning dew has dried, to avoid rainwater entering the wound and causing disease or rot.
(2) Mulching with Grass to Prevent Drought
Atractylodes macrocephala is planted on mountainous land. Because mountain soil has poor structure and weak water-holding capacity, and irrigation is inconvenient, after Grain Rain and before Major Heat, a layer of fresh grass can be spread over the Atractylodes field to prevent excessive evaporation of soil moisture. In plain areas, mulching with grass is also carried out. In addition, plastic film can be used, which both prevents drought and prevents weed growth and the occurrence of disease.
(5) Selecting and Retaining Good Seed
Before removing the flower buds of Atractylodes macrocephala, select plants that are tall, have more branches on the upper part, are robust and uniform, and are free of pests and diseases as seed plants. Keep the early and large flower buds on each plant for seed and cut off the late and small ones to promote plump seed production. After the Start of Winter, when the lower leaves of the plants have withered and aged, cut back the plants together with the stems and hang them in a place with ample sunlight. After 10-15 days, thresh the seed, remove the diseased, pest-damaged and weak seeds, and store them in cloth bags or paper bags in a cool, ventilated place. If a relatively large number of plants are kept for seed and it is inconvenient to cut back the stems, the fruits alone can be picked back and placed in a ventilated, cool place; after drying, thresh the seed and store it for sowing.
(5) Harvesting and Processing
The harvest period is from late October to early November of the year of transplanting (from Frost's Descent to the Winter Solstice), when the stems turn from green to withered yellow and the upper leaves have hardened and break easily. Harvesting too early means the plants are not yet mature, the tubers are tender and the yield after trimming is not high; harvesting too late means new buds sprout and the nutrients of the tubers are consumed. Prevent frost damage, and dig them up on a sunny day when the soil is dry. Dry them in the sun or by baking; sun-drying takes 15-20 days. Atractylodes macrocephala that is frequently turned during sun-drying is called raw sun-dried Atractylodes, and that dried by baking is called baked Atractylodes. When baking, the fire should not be too strong; the temperature should be such that it does not burn the hand. After baking over fire for 4-6 hours, turn it over once, top to bottom; the fibrous roots fall off. Then continue baking until 80 percent dry, take it out and pile it for 5-6 days so that the internal moisture seeps out and the surface becomes soft again, then bake until dry. Atractylodes macrocephala of good quality is large, heavy, free of hollow centers, and white in cross-section. Generally, 2250-3000 kg can be harvested per hectare.
(6) Precautions
Scientific seedling raising: Before sowing Atractylodes macrocephala, turn the soil, cover with weeds, and burn the soil to disinfect it and prevent pests and diseases. Mix the seeds with sandy soil, add New High-Lipid Film, and sow in the field to repel underground pests and diseases, isolate viral infection, strengthen respiration, and increase the seed germination rate. After the seedlings emerge, spray New High-Lipid Film on the plant surface to prevent pathogen infection, improve resistance to natural disasters, improve photosynthetic efficiency, and protect the young plants so they grow robustly.
Rational management When transplanting, select seedlings that are uniform in shape, free of pests and diseases, and have plump buds. Also carry out timely irrigation and drainage, rational fertilization, cultivation and weeding, removal of flower buds, and mulching with grass to prevent drought, and spray the medicinal herb root growth promoter at the appropriate time to promote the transport of leaf photosynthetic products (nutrients) to the root system, improve the nutrient conversion rate and soil-loosening capacity, make the rhizome expand rapidly, greatly increase the medicinal content, promote tuber growth and enlargement, and increase yield. At the same time, strengthen integrated control of pests and diseases, and spray New High-Lipid Film to enhance the control effect. In late autumn, do a good job of cold protection and heat preservation for overwintering to ensure safe overwintering and a good harvest in the coming year.