What Is the Price of Rehmannia Seeds? A Detailed Guide to Planting Methods
The root of Rehmannia (Rehmannia glutinosa) is one of the traditional Chinese medicines, named for its yellow-white underground tuberous root. Also known as Shengdi, Huaiqing Dihuang, and Xiaoji Hejiu, it is a perennial herbaceous plant of the genus Rehmannia in the family Scrophulariaceae. According to processing methods, it is classified in medicinal materials as fresh Rehmannia, dried Rehmannia, and prepared Rehmannia. It is cultivated throughout China and abroad. Let us now take a look at Rehmannia seed prices and planting methods!
How much is a jin of Rehmannia seeds?
The price of Rehmannia seeds is about 50 to 100 yuan per jin, but it varies depending on seed quality, place of origin, variety, and other factors. Rehmannia varieties are mixed, and long-term asexual propagation has led to degeneration, resulting in great differences in yield. Propagation by seed for rejuvenation is one of the means to overcome Rehmannia degeneration. Select high-yielding, high-quality individual plants in the field, collect the seeds and sow them in pots or in the ground, first raising seedlings for one year. The following year, select large and robust rhizomes and move them to the ground to continue propagation. In the third year, select rhizomes with high and stable yield for propagation. By eliminating the inferior and preserving the superior in this way for several consecutive years, excellent varieties can be obtained, with yields often 30 to 40% higher than local varieties.
Growing Conditions for Rehmannia
Rehmannia prefers loose, fertile sandy loam soil; clay-heavy red soil, yellow soil, or paddy soil is not suitable for planting. Rehmannia is a light-loving plant, and the planting site should not be close to forest edges or intercropped with tall-stemmed crops. When the soil temperature is 11 to 13°C, emergence takes 30 to 45 days, and 25 to 28°C is most suitable for germination. Within this temperature range, if soil moisture is suitable, germination occurs one week after planting and seedlings emerge in 15 to 20 days. Below 8°C, rhizomes cannot sprout. From planting to harvest takes 150 to 160 days.
Sowing Methods for Rehmannia
Rehmannia is generally sown in spring, starting when the soil temperature stabilizes above 10°C. Open furrows at a row spacing of 15 cm with a furrow depth of 1 to 2 cm. However, because Rehmannia seeds are tiny, with a thousand-grain weight of 0.15 grams, the soil covering must not be too thick, with about 0.5 cm being appropriate. When propagating by seed, attention must be paid to moisture retention and sowing in time to capture soil moisture. Generally, they are lifted out in the spring of the following year for use as planting stock for production fields. In many places in production areas, after sowing Rehmannia, peas, early-spring dwarf vegetables, and the like are interplanted beside the beds (on the ridges). Interplanted plants are best if dwarf and short-season, and furthermore, interplanted plants should not be too dense.
Planting Methods for Rehmannia
1. Site selection and land preparation: For Rehmannia, choose sandy loam soil with deep soil layers, fertility, and good drainage. At the same time, apply 2000 to 3000 kg of decomposed compost and 25 kg of superphosphate per mu as base fertilizer. Then level and rake the soil fine to make beds. Pay special attention to the fact that Rehmannia should not be planted in continuous cropping.
2. Thinning and filling in seedlings: When Rehmannia seedlings are 10 to 12 cm tall, begin thinning, leaving 1 strong seedling per hole. If there are missing plants, replant promptly on cloudy days. When replanting, lift the seedlings with soil, as this gives a higher survival rate.
3. Cultivation and weeding: Rehmannia rhizomes enter the soil relatively shallowly, so cultivation should be shallow to avoid damaging the roots. Weeds around the seedlings should be pulled out by hand. After the plants close their rows, stop cultivation.
4. Reasonable topdressing: Rehmannia likes fertilizer. In addition to applying sufficient base fertilizer, after thinning, apply 100 kg of superphosphate and 30 kg of decomposed cake fertilizer per mu to promote rhizome development and swelling. When the rows close, broadcast 1 application of burnt soil ash between the rows to promote robust plant growth.
5. Timely irrigation: Rehmannia has a high water requirement in the early stage, so it should be watered frequently. In the later stage, which is the underground rhizome swelling period, water should be used sparingly. During the rainy season, drainage should be done promptly to prevent root rot.
6. Removing surface-creeping roots: In addition to the main root, Rehmannia can also grow slender underground stems along the soil surface, called surface-creeping roots. These surface-creeping roots consume a considerable amount of nutrients, so they should be removed promptly during field management.
7. Disease and pest prevention: The main diseases of Rehmannia include leaf spot, ring rot, and wilt, generally beginning in early May and becoming severe in June to July, so timely prevention and control should be carried out. Pests include red spiders, cutworms, and white grubs, which are controlled by conventional methods.
8. Harvesting and processing: When Rehmannia is planted in spring, it should be dug promptly when the aboveground stems and leaves wither around November of that year. When digging, open a 35 cm deep furrow at one end of the bed and carefully remove the rhizomes in sequence, then use a special roasting oven to process them into prepared Rehmannia, which becomes the commercial product.