Detailed Explanation of the Cultivation Techniques and Management Methods of Rehmannia
Rehmannia, also known as Sheng Dihuang or wild Rehmannia, is the tuberous root of the Scrophulariaceae plant Rehmannia (Rehmannia glutinosa), a perennial herbaceous plant and a traditional Chinese medicinal material. It has the effects of clearing heat and cooling blood, nourishing yin and promoting fluid production, stopping bleeding, and resisting coagulation. It is mainly used to treat conditions such as damage to yin from febrile disease and sore throat, and there is enormous market demand for it. It sells well both domestically and internationally, so many people have become wealthy by cultivating it. So how should it be cultivated? Let's take a look.
1. Land Selection and Preparation
Rehmannia has extremely strong adaptability. Wild plants mostly grow on well-drained sandy land and barren slopes. It likes environments with sufficient sunlight and is suitable for cultivation in loose, fertile soil. If the soil is heavy in clay or hard, it will affect the growth of its tuberous roots and reduce yield. If the soil drainage is poor and water easily accumulates, it will cause the tuberous roots to rot. Continuous cropping should also be avoided; it is best to rotate with crops such as sorghum, vegetables, and cotton for 3-4 years. When planting, plow the soil deeply to 30 cm, apply fertilizer, then plow deeply again, rake it level and fine, and make beds.
2. Seed Selection and Planting
When selecting seedlings for planting, strict standards must be followed. Choose plants that are disease-free and grow vigorously. After selection, break them into small sections about 5 cm in size and air-dry them for 1-2 hours until the wounds heal, then they can be planted. When planting, use a reasonable dense spacing. Generally, about 100 kg of seed is used per mu. After planting, cover with 5-7 cm of soil and water. In low-temperature areas, ground temperature can be raised by covering the ground. As long as temperature and moisture are suitable, seedlings generally emerge in 25-30 days.
3. Fertilizer and Water Management
When fertilizing Rehmannia, apply more phosphorus and potassium fertilizer. In addition, applying sufficient base fertilizer is also extremely important for yield. After the seedlings are uniform, to make the seedlings grow quickly, topdress while watering. At this time, apply 15 kg of urea per mu, which can be dissolved in water and applied as a liquid fertilizer, or apply fertilizer and then water immediately to speed up nutrient absorption. In the mid-growth stage, that is, in July, topdress with 10-20 kg of phosphorus fertilizer per mu. During the growth of Rehmannia, water frequently to keep the soil moist. However, in the late growth stage, when the tuberous roots are growing, it is afraid of water accumulation, which can easily cause root rot. Therefore, at this time, watering should follow the principle of not watering unless there is drought, not watering on cloudy days, and not watering at noon.
4. Field Management
When the seedlings grow to more than 10 cm, thin them in time, leaving one plant per hole. If plants are missing, replant them. Replanting should be done on cloudy days, and it is best to transplant with soil attached. In the early growth stage of the plants, the seedlings are too small and the root system is relatively shallow. At this time, weed to avoid affecting seedling growth. Weeding should be done by shallow hoeing, or by hand pulling, so as not to damage the root system. If planting on a large scale, it is recommended to use herbicides. During the growth of Rehmannia, in addition to the main root, some slender underground stems will also grow, called string-skin roots. They consume a large amount of nutrients from the plant and should be cut off in time.
The above are the cultivation techniques for Rehmannia. We hope this can help you. To learn more about medicinal herb cultivation knowledge, please stay tuned to us.