Planting techniques of Rehmannia glutinosa

Rehmannia glutinosa, also known as Rhizoma Rehmanniae, belongs to the genus of Scrophulariaceae. It has the effects of cardiotonic, diuretic, analgesic, hypoglycemic and liver protection. it can be cultivated all over the country. The main techniques and key production measures of high-yield cultivation of Rehmannia glutinosa are as follows.

Land selection and preparation

It is appropriate to choose sandy loam with deep, fertile and good drainage. Turn the soil more than 25 cm deep in the first winter or early spring and apply 2000-3000 kg of rotten compost per mu and 25 kg of superphosphate as base fertilizer. Then, leveling and raking fine to make the border, the general width of the border is 1.3 meters. Special attention should be paid to the fact that Rehmannia glutinosa should not be replanted, which is also a key measure that should be paid attention to in the selection of land.

Seed selection and planting

Generally cultivated Rehmannia glutinosa uses rhizome as propagation material, which is called & # 39; planted & # 39; Rehmannia glutinosa & # 39; planting & # 39; generally selected & # 39 planted in July-August of the previous year; inverted & # 39; planting & # 39; this is because & # 39; inverted & # 39; planting & # 39; when used as a seed, Rehmannia glutinosa has high yield, good quality and can prevent variety degradation. Before planting, cut off the head and tail of the plant and take the middle section. Then cut into small sections 3-6 cm long, each section should leave two to three bud holes, the incision should be stained with plant ash, and then planted after slightly drying, generally planting density row spacing 30-40 cm, plant spacing 25-30 cm, dig a hole 3-5 cm deep on the whole border surface, put each hole horizontally & # 39, cover 1-2 sections with dung water, cover with fine soil cover and border. It needs 40-60 kg per mu. Note that when selecting seeds, try to use & # 39; inverted & # 39; planting & # 39; avoid using small commodities; at the same time & # 39; remove & # 39; old mother and son & # 39; That is, it was planted in the first ten days.

Field management

1. And time to replenish seedlings. When the height of the seedling is 10-12 cm, the seedlings begin to grow, leaving 1 strong seedling in each hole. If there is a lack of plants, they should be replanted in time in cloudy days, and the seedlings should be raised with soil when replanting, so that the survival rate is higher.

2. Ploughing and weeding. The rhizome of Rehmannia glutinosa is shallowly buried in the soil, and the middle tillage should be shallow to avoid root damage. The weeds around the seedlings should be pulled out by hand. After the plants are closed, the middle tillage should be stopped.

3. Topdressing. Rehmannia glutinosa likes fertilizer. In addition to applying sufficient base fertilizer, 100 kg of superphosphate and 30 kg of rotten cake fertilizer are applied per mu after interseedling to promote the development and expansion of rhizome. When the row is closed, fire soil ash is applied once between rows to promote the healthy growth of plants.

4. Irrigation. Rehmannia glutinosa needs a lot of water in the early stage, so it should be watered frequently, and in the later stage, it is the period of underground rhizome expansion, so water should be saved. Attention should be paid to timely drainage in the rainy season to prevent the occurrence of root rot

5. Except for the string of skin roots. In addition to the main root, Rehmannia glutinosa can also grow slender underground stems along the surface, called string bark roots, which lose a lot of nutrition and should be eradicated in time.

Prevention of diseases and insect pests

The diseases of Rehmannia glutinosa are mainly spot blight, ring disease and Fusarium wilt, which generally begin to occur in early May and are serious from June to July, so we should pay attention to timely control; pests include red spiders, ground tigers, grubs and so on, which are treated according to conventional methods. pay attention to avoid the use of highly toxic pesticides when choosing pesticides.

Harvest and processing

Rehmannia glutinosa planted in spring should be picked in time when the aboveground stems and leaves are withered and yellow around November of that year. When digging, you should open a 35-centimeter deep trench at one end of the border and carefully pick the rhizome in turn; processed Rehmannia glutinosa uses a special oven to process it into cooked land, that is, into a commodity.