When to plant Isatis root (banlangen) and how long its growing period lasts
With the development of technical conditions, the planting conditions for Isatis root have also been gradually improving, but the ultimate purpose of growing Isatis root is profit, so the planting method that maximizes profit is the one growers need, and profit maximization is ultimately built on complying with natural laws.
Planting time for Isatis root
Different sowing seasons for Isatis root yield different products. According to the sowing time, Isatis root can be divided into 4 stages: autumn sowing, early spring sowing, spring sowing and summer sowing. Autumn sowing and early spring sowing are mostly aimed at harvesting seeds; the roots of Isatis root planted in these two periods cannot be used as medicinal material. Summer sowing is suitable for areas in the south with a relatively long plum rain season; this method can reduce pests and diseases, but the yield is lower. Spring-sown Isatis root can yield both leaves and roots, and the yield is relatively high, making it the most commonly used method.
How long is the growing period of Isatis root
The growing period of Isatis root is about 8 to 9 months.
Sowing methods for Isatis root
1. Soil selection: Isatis root is a deep-rooted plant. It is suitable for a warm and humid climate, is drought-resistant and cold-resistant, and fears waterlogging; after being soaked in water, its roots rot easily. It can be planted in ordinary soil, but it is best to choose loose soil with good drainage.
2. Land preparation and fertilization: When preparing the planting site for Isatis root, combine deep plowing with rational fertilization. Apply 3000-4000 kg of farmyard manure, 15 kg of diammonium phosphate and 4 kg of biological potassium fertilizer per mu, spread them evenly in the field and plow more than 30 cm deep, then make flat beds 1 m wide.
3. Sowing time: In northern China, Isatis root is suitable for spring sowing and should be sown late at the right time. If sown too early, it bolts and flowers early, which not only reduces yield but also lowers the quality of Isatis root. The most suitable time is April 20 to 30.
4. Sowing method: Before sowing Isatis root, soak the seeds in warm water at 40-50 degrees C for 4 hours, then remove them and mix them evenly with plant ash. Open furrows on the bed surface, scatter the seeds evenly into the furrows, cover with soil and press lightly, water appropriately to keep moist; at a suitable temperature, seedlings emerge in 7-10 days.
Prospects for growing Isatis root
Isatis root is one of the commonly used bulk Chinese medicinal materials in China, with the effects of clearing heat and detoxifying, cooling blood and benefiting the throat. Its antiviral effect is the most obvious, and it is a good medicine for preventing and treating epidemic diseases such as influenza, mumps, Japanese encephalitis and infectious hepatitis. Therefore, historically, whenever epidemics or diseases were found in various places, Isatis root was present. Since China's reform and opening up last century, the market for Isatis root has fluctuated greatly under the influence of various factors. For example, in 1987, when Shanghai suddenly had an outbreak of epidemic infectious hepatitis, Isatis root soared from about 2 yuan (price per kg, the same below) before the incident to a high price of 22 yuan; the second time was in the spring of 2003 during “SARS”, when in Guangzhou, the city with the most severe epidemic, it once rose to more than 100 yuan at the highest; the third time was in 2005 when avian influenza occurred in some areas of China, and prescriptions were also mainly based on Isatis root. It is not hard to see that the glorious history of Isatis root is closely linked to sudden epidemics.
Because of the obvious antiviral effect of Isatis root, new products have been continuously launched in recent years, and sales of Isatis root have continued to increase. In recent years, annual sales of Isatis root have stayed at around 15,000 tons (except during SARS in 2003). Medicines using Isatis root as the main raw material include: Isatis root granules, Isatis root injection, Isatis root syrup, Isatis root tablets, Isatis root lozenges, Isatis root tea and so on. Among them, Isatis root granules are well known; they are cheap, convenient to take, obviously effective and free of side effects, and are a good medicine for preventing colds in spring, autumn and early winter, with huge sales.
Isatis root is also used in large amounts in veterinary medicine. With the continuous development of China's breeding industry, various livestock diseases occur frequently, such as the avian influenza that occurred this year. The antiviral effect of Isatis root is obvious, and its annual sales in veterinary use are also more than 2000 tons.
In addition, since 2004, Isatis root began to see large-scale abandonment or reduction of planting. There are mainly two reasons: first, under the influence of national preferential policies such as rising grain prices and direct subsidies for grain growing, farmers abandoned medicinal herbs to grow grain, and the area planted with medicinal herbs decreased year by year; second, when Isatis root was at its peak, the price was extremely high, and when the market slumped, the price fell and was hard to recover, with price changes being dramatic, sudden and persistent. In addition, Isatis root easily changes color, loses oil and gets infested with insects, making it difficult to store for a long time. As a result, producers and operators miss opportunities with every price fluctuation, and farmers in producing areas suffer the most.
In view of the above reasons, people in the pharmaceutical field predict that the prospects for developing Isatis root are broad. It is hoped that favorable opportunities will be seized to develop Isatis root planting according to GAP standards.
Isatis root is a medicinal material with relatively large current market demand and is also a commonly used bulk medicinal material in China, so under ordinary conditions, growing Isatis root can currently achieve relatively good profits, and in the future, the development prospects of Isatis root will remain broad.