Detailed Explanation of Key Points of New High-Yield Coptis chinensis Cultivation Techniques

Coptis chinensis, also known as Zhonglian, Yalian and Chicken-Claw Coptis, grows in moist, shady, preferably north-facing, neutral soil zones at an altitude of 900-1500 m. Coptis chinensis is a perennial herbaceous plant of the Ranunculaceae family. It has many varieties and a wide growing range, and is divided into wild and cultivated types (the wild type is superior in quality). The seedling growing period is 1 year, and the period after transplanting is 4 years, with a plant height of 15-45 cm.

I. Seedling Raising

1. Seed collection and storage. Coptis plants grown for 2-4 years all flower and set seed. The harvest season is every summer. At harvest, gently pick the seed stalks and put them into cloth bags, dry them in the shade, and remove the husks and debris to obtain pure Coptis chinensis seeds. For dormant seed storage, the usual method is mixing with sand and mud: mix 1 kg of Coptis chinensis seeds into 3 kg of moderately dry and wet sand and mud, then seal them in a breathable cloth bag and place it in a cool, ventilated place. Check regularly; it is best if the mixture holds together when squeezed by hand and crumbles apart when the hand is opened. If the sand-seed mixture is found to be too dry, spray a small amount of clean water to keep it moist, and wait until autumn or winter to sow it in the ground.

2. Land preparation and frame building. The Coptis chinensis seedling bed should be chosen on fertile virgin land. Remove tree roots and weeds, dig shallowly with a hoe to a depth of 10 cm, and open beds with 1.5 m spacing between furrows, breaking the soil up fine and leveling it. Build a shade shed: drive a wooden stake every 2 m along the middle of the bed, with the stakes about 2.2 m long and their tops shaped like a "Y" to make it easy to lay bamboo and wooden crossbars and branches for shade.

3. Sowing and shading. The best sowing time is late autumn to early winter. Use about 0.5 kg of pure seed per mu, which counts as 2 kg of sand-mixed seed, and sow evenly. Then cover with tree branches to protect against sun and rain, and also to retain moisture and prevent drought, raise the seedling emergence rate, and promote strong and uniform seedlings. Each mu of seedling nursery produces 100,000 seedlings, enough to transplant to a production area of 3-4 mu.

4. Fertilizing and disease prevention. Careful management at the seedling stage is crucial. The sown seeds begin to sprout and grow when the temperature rises in early spring. When inspection finds that more than 60% of the seeds have germinated and turned green, the covering should be removed, and the branches should then be laid evenly on the shade frame, followed by clearing away dead branches, fallen leaves and weeds on the seedling bed. Once the Coptis seedlings have more than 4 leaves, seedling fertilizer can be applied, using 0.5-1 kg of urea per mu, either broadcast dry or dissolved in water and sprayed, once each in spring, summer, autumn and winter. Broadcasting plant ash can prevent powdery mildew, at 50 kg per mu; after application, gently sweep the plant ash off the leaves with bamboo or tree branches to avoid burning the seedlings. If the seedlings develop downy mildew and powdery mildew, 1 kg of quicklime can be spread per mu, or 25% carbendazim wettable powder can be diluted to a 500-fold solution and sprayed, or alternately 50% thiophanate-methyl wettable powder at 1000-1500-fold dilution can be sprayed, once every 5-10 days, for 2-3 consecutive sprays with good results.

II. Cultivation

Coptis chinensis grows in zones at an altitude of 900-1500 m. It prefers shade and tolerates little sun, and needs abundant water and nutrients. It can be harvested 4-5 years after planting.

1. Selecting strong seedlings for planting. Coptis seedlings can be raised yourself or purchased. Generally, 1-1.5 year old disease-free tender seedlings and strong seedlings are best for transplanting and give the best yield. Seedlings over two years old are old and weak and give lower yields after planting, so they should not be chosen. For Coptis production, virgin land is best because it has fewer weeds and fewer pests and diseases. Land selection and preparation are basically the same as for the seedling bed, and some trees can be left to provide shade.

2. Careful planting. Coptis seedlings can be planted in all four seasons, but spring and autumn are the best seasons. The planting method is one plant per hole, with a hole and row spacing of about 15 cm, in a square arrangement. When planting, press the fibrous roots firmly with fine soil, keep the crown of the seedling level with the soil surface, and do not plant too deep.

3. Weeding and earthing up. Management of the Coptis planting is the main guarantee of a high yield. Weed to protect the seedlings, weeding three times a year in spring, summer and autumn, while in winter earthing up is the main task. Coptis tillers each year and sends up a new batch of buds above the soil surface; earthing up can promote vigorous rhizome growth. The method is to dig fertile soil from the bed furrows and field edges and spread it evenly over the Coptis beds. Before earthing up, apply a base fertilizer once, using 50 kg of plant ash and 50 kg of compound fertilizer per mu, then cover with soil.

4. Topdressing and disease prevention. Spring and autumn are the periods of vigorous growth for Coptis and also the times of greatest nutrient demand. Apply urea once each in autumn and the following autumn, using 5 kg per mu each time. Coptis beds two years after planting should be given additional human and livestock manure to promote root growth.