How to Grow Isatis Root (Banlangen)? A Detailed Guide to Cultivation Methods
Everyone should be very familiar with isatis root (banlangen); it is a very well-known Chinese medicinal herb, and the banlangen granules we commonly take are made from processed isatis root. In China, the consumption of isatis root is very large, and during periods when colds are prevalent, demand often exceeds supply. Growing isatis root is also a great business idea!
Cultivation Methods for Isatis Root
One week before sowing, water thoroughly once to ensure the moisture needed for isatis root seeds to germinate and take root. There are many sowing methods for isatis root, but the commonly used methods are drilling and hole sowing.
Drilling uses a row spacing of 30 cm, with a sowing rate of about 3 kg per mu; hole sowing uses a row and plant spacing of 30×20 cm or 30×30 cm, with less seed used, between 1.5-2 kg per mu. The sowing depth is 3 cm. After sowing, cover with a layer of fine soil, with a covering thickness of about 1 cm, and finally cover the bed surface with plastic film to retain moisture. Because spring winds are strong, to prevent the wind from blowing up the plastic film, after covering the bed surface with the film, in addition to pressing the edges firmly with soil, soil should also be pressed in the center of the film.
How to Grow Isatis Root
1. Seed selection
The seeds of isatis root should be new seeds harvested the previous year, with black on the seed coat. Such seeds have good maturity, and the germination rate can be guaranteed to be above 95%. Moreover, such seeds will not bloom in the same year after sowing; whereas if seeds stored for many years are chosen, not only is the germination rate low, but they also tend to bloom in the same year, affecting the yield and quality of isatis root.
2. Seed treatment
After the seeds are selected, in order to improve the germination rate of isatis root seeds, the seeds must also be treated before sowing. First soak the seeds in clean water for 12-24 hours. This can, first, remove grass debris and shriveled seeds mixed in with the isatis root seeds, and second, soften the seed coat of the isatis root seeds to facilitate sprouting. After soaking, remove and dry them, and then they are ready for sowing.
3. Sowing time
In the cultivation process of isatis root, there are strict requirements for both sowing time and sowing methods. First let us understand the sowing time. For spring-sown isatis root, northern regions generally sow in early April, while southern regions can sow appropriately earlier, but sowing is only allowed when the local temperature is stable above 12°C, which helps the root system grow deep and extends the growth period.
Field Management
1. Thinning and final singling: After emergence, when the seedlings are 7~8 cm tall, thin to a plant spacing of 6~10 cm, removing weak seedlings and keeping strong ones, and fill in gaps where seedlings are missing. When the seedlings are 10~12 cm tall, combine final singling with cultivation and weeding, setting the plant spacing at 6~9 cm and row spacing at 10~15 cm.
2. Cultivation and weeding: Shallow cultivation after the seedlings emerge, and cultivation after final singling. When weeds have 3~5 leaves, selective herbicide of the quizalofop-p-ethyl type can be sprayed to control grass weeds, with 40 ml of pesticide per mu, diluted with 50 kg of water for spraying.
3. Topdressing and watering: For those mainly harvesting Daqingye (isatis leaves), topdress 3 times each year. The first time is after planting, opening shallow furrows between the rows, applying 10~15 kg of urea per mu, and watering promptly to retain moisture. The 2nd and 3rd times are topdressing after harvesting Daqingye; to make the plants grow robustly and vigorously, farmyard manure can be used with an appropriate application of phosphorus and potassium fertilizer; for those mainly harvesting isatis root, do not cut Daqingye during the vigorous growth period, and apply less nitrogen fertilizer, with an appropriate application of phosphorus and potassium fertilizer and plant ash, to promote thick and large root growth and increase yield.
Pest and Disease Control
Diseases: Mainly downy mildew and root rot. Downy mildew causes pale green lesions on the leaves, and when it occurs, white or grayish-white mold-like substances appear on the underside of the leaves, and in severe cases the leaves wither and die; root rot mostly occurs in the rainy season, causing the roots to rot and leading to the death of the whole plant. Control methods: Give priority to agricultural control, carry out reasonable crop rotation with grass family and legume plants, maintain reasonable close planting, improve ventilation and light conditions, and promptly remove diseased leaves and diseased plants, take them out of the field, and bury them deeply in a centralized manner; 65% zineb or 77% copper hydroxide wettable powder can also be used for spraying or root drenching.
Pests: Mainly cabbage caterpillars and diamondback moths. Cabbage caterpillars bite and eat the leaves, causing holes and notches in the leaves, and in severe cases leaving only the leaf veins; diamondback moths bite and eat the leaves, initially causing “skylights” and later causing notches and holes, leaving only a net-like leaf vein pattern. Use diflubenzuron No. 3, BT emulsion, or 90% trichlorfon at 1000 times dilution for spray control.
Through the above content, I believe everyone has a better understanding of the cultivation techniques for isatis root. In China, almost every household keeps a large packet of isatis root on hand to guard against colds and coughs. Growing isatis root has high yield and low capital input, yet the profit is very considerable, and the cultivation prospects are even broader!