How to grow Gastrodia elata for high yields? A detailed guide to the latest cultivation techniques
Gastrodia elata is a precious Chinese medicinal herb, containing nutrients such as gastrodin, calcium oxide, magnesium oxide, vanillyl alcohol, and vitamin A. It has the functions of dispelling wind and relieving convulsions, relieving pain, resisting convulsions, and lowering blood pressure. It mainly treats headache, dizziness, high blood pressure, rheumatic waist and knee pain, numbness of the limbs, infantile convulsions, insomnia, and cerebrovascular diseases. It has important value in medicine, and currently the product is in short supply, with prices rising year after year, reaching more than 200 yuan per kilogram, and export prices are even more expensive. Gastrodia elata used to be wild, generally growing in mountain forests at an altitude of 500-1500 m, with scarce yields and very difficult to collect. Developing artificial cultivation of Gastrodia elata has broad prospects: sow in the same year and harvest in the same year, with a yield of 20-30 kg per sq m and an income of 500-600 yuan, giving very high economic benefits. The latest high-yield cultivation method is introduced as follows: Cultivation of Armillaria mellea. Gastrodia elata has a symbiotic relationship that is both parasitic and saprophytic, and mainly depends on Armillaria mellea to provide nutrients in order to grow. Therefore, to cultivate Gastrodia elata, Armillaria mellea must first be cultivated.
1. Selection of fungal wood:
Any broadleaf tree can be used as fungal wood, but oak species (Quercus acutissima, also known as green oak) and cherry trees are the best. Whether branches or branch forks, all can be used as fungal wood, but fungal wood with a diameter of 5-8 cm is better. The tree-cutting season should be chosen when new buds appear each year; generally cut trees in February to March, saw them into 1-meter lengths, place them in the sun and air-dry them for 1-2 months to let them die as quickly as possible, and they can be used for fungal inoculation in April to May.
2. Fungal inoculation:
Fungal inoculation can be done either on flat ground indoors or in outdoor beds. First spread a layer of sandy soil about 3-5 cm thick on the ground, with a width of 1 m and unlimited length, then cut slanted notches every 15-20 cm into the prepared wooden sticks and place them side by side on the sandy soil, sprinkle on the previously cultivated Armillaria mellea spawn, and cover with sandy soil to a level 2 cm above the stick surface. Then, in the same way, place a second layer of wooden sticks and sprinkle spawn, and in this order place 4-5 layers. Finally cover the top with 10 cm thick sandy soil. To maintain a certain moisture and dampness in the sandy soil, straw mats or plastic film can also be placed over it, and water can also be applied regularly to retain moisture. In the fungal inoculation process, the key is the management of temperature and humidity. The suitable temperature for Armillaria mellea growth is 10-28 degC, but the most suitable is 18-22 degC. During fungal inoculation, adjustments can be made according to the natural air temperature and the stacking density of the fungal sticks. In particular, during mycelial growth it itself generates a certain amount of heat, so at this time it is necessary to consider that the temperature inside the pile should preferably not exceed 25 degC. Humidity should be kept so that the sandy soil water content is 50%, preventing excessive dryness or water accumulation from affecting mycelial growth. After more than two months of cultivation, Armillaria mellea has covered the entire wooden sticks and become fungal wood. At this time, depending on the scale of Gastrodia elata cultivation, decide whether to expand the fungal wood cultivation. The method of expanding fungal wood cultivation is to use fungal wood to propagate fungal wood, alternating old and new according to the above inoculation method, and it can also be stacked in a "#" shape for fungal inoculation. Gastrodia elata cultivation. The Gastrodia elata cultivation season runs from November to April of the following year. Except for the coldest "Sanjiu" period or snowy days, it can be cultivated at other times (because too cold will freeze and damage Gastrodia elata). It is best to choose March or November for cultivation. If cultivated in March, it can be harvested in November of the same year or March of the following year; if cultivated in November, it is harvested in November of the following year.
Cultivation methods: There are many ways to cultivate Gastrodia elata. Two methods, indoor and outdoor, are introduced here.
1. Indoor flat-ground cultivation: Gastrodia elata can be cultivated in a room of any size, preferably a house that is warm in winter and cool in summer, with an indoor temperature between 10-25 degC. A basement or air-raid shelter gives the best effect. The cultivation method is to first spread 3-5 cm of sandy soil on the ground, then place fungal wood on the sandy soil, one old and one new, at a distance of 10-15 cm. Between the old and new fungal wood, fungal branches can also be placed horizontally, one old and one new, at a distance of 10-15 cm. Fill with sandy soil until half of the fungal wood is covered, then place Gastrodia elata seeds, with the seeds placed upright along both sides of the fungal wood, with 12-15 cm between each tuber. Then cover with sandy soil to 2-3 cm above the fungal wood, sow the second layer in the same way, and finally cover with 7-10 cm thick sandy soil. Cover the outside with plastic film to retain heat and moisture (if using a basement that can retain heat and moisture, the film may be omitted).
2. Outdoor bed cultivation: For outdoor bed cultivation of Gastrodia elata, first choose a place that does not accumulate water, or a sloping field, to make the bed; second, use underforest areas or artificial shade sheds, and methods such as laying straw mats or planting green grass can also solve the problem of direct sunlight, so that Gastrodia elata can obtain high yields. After choosing the site, dig a flat-bottomed bed 40 cm deep from level ground, with the width determined by the length of the fungal wood and unlimited length. First spread 5 cm thick sandy soil at the bottom, arrange new and old fungal wood at intervals of 10-15 cm, then place new and old fungal branches horizontally to connect the new and old fungal wood so they transmit fungi to each other. Fill with sandy soil until half of the fungal wood is covered, then place Gastrodia elata upright along both sides of the fungal wood at a distance of 12-15 cm, then cover with 5-6 cm of sandy soil, sow the second layer in the same way, and finally cover with 7-10 cm thick sandy soil (it may be level with the ground or higher than the ground). Cover the outside with plastic film plus straw mats, or plant green grass as a shade measure to lower temperature and retain moisture. Management techniques for Gastrodia elata. After sowing Gastrodia elata, whether indoors or outdoors, the main task is the management of temperature and humidity.
1. Temperature: The suitable growth temperature for Gastrodia elata is 12-25 degC, but the most suitable is 15-22 degC. Above 25 degC or below 10 degC, growth stops; above 30 degC or below 2 degC, it quickly dies. Therefore, grasping and controlling temperature is the key in Gastrodia elata growth. If the temperature is too low, plastic film covering plus straw mats can be used to retain heat; if the temperature is too high, cooling methods such as covering with straw mats, building shade sheds, and planting green grass can be used. In short, achieving warmth in winter and coolness in summer is the ideal environment for Gastrodia elata growth.
2. Humidity: If indoor cultivation of Gastrodia elata is dry, the surface of the sandy soil can be covered with plastic film to retain moisture. For outdoor cultivation, it is necessary both to retain moisture and prevent dryness, and to prevent rainwater erosion and water accumulation. Drainage ditches can be dug around it. If drought occurs, water can be sprinkled to retain moisture, or plastic film plus straw mats can be used for covering. In short, keep the surface layer of the sandy soil somewhat moist, with a water content of 50-55% being suitable.
3. After Gastrodia elata is cultivated, do not turn or disturb it, and prevent trampling by people and livestock and insect damage.
To prevent pests from entering the site, ditches can be dug around the Gastrodia elata cultivation site, and lime powder or other insecticides can be scattered in the ditches. Harvesting and processing of Gastrodia elata
1. Harvesting: Harvesting and cultivation of Gastrodia elata are carried out at the same time; generally, harvest, collect, and sow at the same time. Select the commercial tubers (large tubers) to process into commercial products, while white-headed tubers and rice tubers continue to be used as seed and are cultivated promptly. Add new wood to the original fungal wood and cultivate according to the above method. Harvesting method: first dig away the surface sandy soil, take out the fungal wood, then take out the commercial tubers, white-headed tubers, and rice tubers and place them separately in baskets, preventing damage to the Gastrodia elata during digging, which would affect quality.
2. Processing: After harvesting, Gastrodia elata should be processed promptly; otherwise it will continue to grow or bolt, consuming nutrients and becoming hollow inside. There are many methods for processing Gastrodia elata. The following two are introduced for selection.
(1) Rinse the dug fresh Gastrodia elata with clean water to remove soil, air-dry it, then put fine sand into a wok and stir-fry until the sand turns red (when a piece of torn paper placed in it catches fire). At this point, add the Gastrodia elata and keep stirring continuously. The time should be short, and stir-fry until the outside of the Gastrodia elata is scorched while the inside remains raw, until the sound becomes quieter, then take it out. Then place it into a prepared basin of cold water, and while hot, gently scrape off the rough outer skin of the Gastrodia elata with a bamboo knife. After washing clean, place it in alum water and soak for about 10 minutes, then take it out for drying. Finally, fumigate it with charcoal fire plus sulfur until completely dry, and it becomes a semi-transparent milky-yellow commercial-standard tuber.
(2) Simple processing method: After rubbing off the rough skin of fresh Gastrodia elata with rice husks, soak it in alum water for 10 minutes, then rinse it clean with clean water and steam it in a steamer until it looks transparent when held up to light. Then dry it over a fire or in the sun until 60-70% dry, press it flat with a wooden board, then fumigate it over a slow fire with sulfur until completely dry, and it becomes a transparent commercial product. After the Gastrodia elata is dry, put it in plastic bags to keep it moisture-proof for storage.