How to grow Anoectochilus roxburghii? Detailed cultivation techniques for the medicinal herb Anoectochilus roxburghii
Site selection and land preparation
Anoectochilus roxburghii prefers a shady, cool and humid habitat, so for cultivation it is best to choose a site with open terrain, facing south with its back to the north, surrounded by tall broadleaf forest, and far from pollution sources.
Planting methods
1. Building the greenhouse: Artificial cultivation requires simulating the growing environment of wild Anoectochilus roxburghii. Build a steel-frame greenhouse with strong wind resistance, oriented north-south, with a length of 25-30 m, a width of 15-20 m, a height of 5-6 m and an eave height of 3-3.5 m. Cover the roof and all sides first with plastic film and then with shade netting, so that the temperature, light and humidity inside the greenhouse can be controlled manually. Where conditions permit, install air conditioning, exhaust fans, a water curtain system and a micro-sprinkler irrigation system.
2. Installing the growing racks: To make full use of space and increase the number of plants per unit area, production usually uses growing racks to hold growing trays, with the growing medium placed in the trays. The racks are 1 m wide and 1.5 m high, with the length depending on the greenhouse. There are 3 growing tiers, with 45 cm between tiers. To facilitate routine management and maintain good ventilation, a spacing of 60-80 cm should be kept between two rows of racks.
3. Cropping schedule: To avoid the effects of low temperatures in January-February and high temperatures in July-August on the growth of Anoectochilus roxburghii, production usually involves two growing seasons per year. The first season is transplanted in early March and harvested in late June; the second season is transplanted in early September and harvested in late December. This ensures the plants grow in the soil for more than 4 months, thereby increasing yield and the medicinal components of the product.
4. Selection of growing medium: Anoectochilus roxburghii prefers loose, fertile soil. For artificial cultivation, the growing medium is usually prepared in the ratio peat soil : rice husk : fine sand = 10:1:1. Before planting, the growing medium is disinfected by sun exposure, then for every 100 kg of growing medium, 5-7.5 kg of slaked lime or an appropriate amount of 50% carbendazim wettable powder is added and mixed thoroughly. The optimum pH for growth is 5.4-5.6.
5. Variety selection: At present, the Anoectochilus roxburghii grown in Longyan includes Fujian varieties and Taiwan varieties, both of which have good adaptability and are favored by consumers. In particular, the wild Anoectochilus roxburghii of Liangye Mountain and Guanzhai Mountain sell very well on the market after artificial cultivation. The Taiwan varieties, however, are relatively sensitive to low temperatures.
6. Tissue-cultured seedlings: Anoectochilus roxburghii has small seeds, a low natural reproduction rate and a low cutting propagation coefficient, so large-scale artificial cultivation should use tissue-cultured seedlings. May is the best time to collect explants. Planting tissue-cultured seedlings can maintain the excellent traits of the mother plant and produces uniform plants. Select bottled tissue-cultured seedlings that have been hardened in a greenhouse for more than 15-30 days, with a plant height of 3-6 cm and 2-3 leaves. Wash away the culture medium with clean water, soak in a 5% carbendazim solution for 10-12 min, then remove, air-dry the surface water, and transplant as tissue-cultured seedlings for greenhouse cultivation.
7. Reasonable close planting: To achieve the highest population yield, plant at a spacing of 2 cm × 5 cm, transplanting 140-150 plants per growing tray. Before planting, wash the seedlings clean with water. When planting, keep the depth at about 1 cm; deep planting should be avoided. After planting, spray with an 800-1000 times dilution of 45% metalaxyl-hymexazol wettable powder.
8. Management after planting: One month before Anoectochilus roxburghii matures, depending on its growth, spray with a 0.1% urea solution as a nutritional supplement. One week after transplanting, spray once every 7 days with a 500 times dilution of 10% amino acid (stop use 15 days before harvest). On the 7th day after planting, spray a mixed solution of 0.13% Previcur and 0.33% Admire to control bacteria and insects. Within 15 days after transplanting, use plastic film covering and control the temperature and humidity in the greenhouse well. The temperature should be between 20-27°C and the relative air humidity should be kept at 70-80%. If the temperature is obviously too high, shade netting can be covered and the micro-sprinkler irrigation facility turned on to lower the temperature and increase humidity, so as to prevent leaf scorch caused by high temperatures. The substrate humidity should be maintained at 70-75%.