Detailed Explanation of Practical Technical Points for Scutellaria baicalensis Cultivation

The Chinese medicinal herb Scutellaria baicalensis is a perennial herbaceous plant of the Lamiaceae family, with its roots used as medicine. It has antibacterial and anti-inflammatory, blood pressure-lowering and diuretic, detoxifying and cholagogic effects, and is also a commonly used traditional Chinese medicine. It is produced in Hebei, Liaoning, Shaanxi, Shandong, Inner Mongolia, Heilongjiang and other provinces and regions, and can be cultivated in most provinces and regions of northern China.

Scutellaria baicalensis prefers warmth and tolerates severe cold; its underground parts can endure temperatures as low as -30°C. It is drought-tolerant but afraid of waterlogging; when planted in poorly drained or rainy areas, the growing environment causes poor growth and easily leads to root rot.

I. Planting Methods

Scutellaria baicalensis is mainly propagated by seed, and can also be propagated by cuttings and root division.

1. Seed propagation: Direct seeding is generally used. Because the seeds are small, seedling emergence is relatively difficult, so the land must be well prepared. Before land preparation, apply 2000-3000 kg of decomposed farmyard manure per mu, plow deeply and harrow finely. The seedbed surface should be fine and level; sloping land without irrigation conditions does not need to be made into beds. Spring sowing is in March and April; summer sowing can be done during the rainy season, and winter sowing is also possible. Spring sowing gives the highest yield; in places without irrigation conditions, sowing should be done during the rainy season. Drilling is generally used, with row spacing of 25-30 cm, opening shallow furrows 2-3 cm deep, sowing the seeds evenly into the furrows, covering with about 1 cm of soil, and gently pressing after sowing. The sowing rate is 0.50-1 kg per mu. Because the seeds are small, to avoid uneven sowing, 5-10 times fine sand can be mixed in and stirred evenly before sowing. Water promptly after sowing and keep the surface soil moist frequently; seedlings will emerge in about 15 days. After emergence, thin out the overly dense weak seedlings. When the seedlings are 6-7 cm tall, thin to a plant spacing of 12-15 cm, and fill in gaps where seedlings are missing. When filling gaps, be sure to transplant with soil; dense seedlings can be moved over to fill the gaps, and water after planting to help survival.

Scutellaria baicalensis seeds are small, and the soil covering at sowing is shallow. Seedling emergence is often difficult because of soil drought or uneven surface soil with large clods, resulting in many missing seedlings. Solutions: first, the land must be prepared finely and leveled; second, water promptly after sowing and keep the soil moist frequently until emergence; in addition, for dryland planting, choose sowing during the rainy season, or use plastic film mulching or straw mulching to preserve soil moisture, and remove the mulch once seedlings emerge. In this way, uniform and neat emergence can be ensured.

2. Cutting propagation: The most suitable period for cuttings is May and June, when the plants are in vigorous vegetative growth. Cut the semi-lignified young tender upper portions of stems and branches (cuttings from the middle and lower parts of stems have a very low survival rate) into 6-10 cm lengths, then remove the leaves from the lower 2 nodes and keep the upper leaves. The cutting bed is best made of sand, or relatively loose sandy loam is also acceptable. Generally, cut and insert immediately, placing them in the bed at a row spacing of 10×5 cm. Water promptly after insertion, set up a shade frame, and spray water frequently to keep the soil moist, but not too wet, otherwise the cuttings will turn black and rot. With proper management, the survival rate can reach over 90%, and they can be transplanted 40 days after cutting.

3. Root division propagation: At harvest, pay attention to selecting high-yield and high-quality plants; cut off the roots for medicinal use and keep the rhizome portions as propagation material. If harvested in winter, bury the rhizomes indoors in a cool place and divide and plant them in the second spring; if harvested in spring, dig and plant immediately, dividing the rhizomes into several pieces, each with a few bud eyes, and then plant them in the field at a row spacing of 30×20 cm. On sloping land, this method gives a relatively high survival rate, and management after planting is the same as usual.

II. Field Management

During the emergence stage, keep the soil moist frequently and water promptly when the soil is dry. After the plants become established, their drought resistance increases, so watering can be reduced; during the rainy season, attention should also be paid to drainage and waterlogging prevention. At ordinary times, also pay attention to loosening the soil and weeding at any time. In addition to strengthening general management, attention should also be paid to fertilization. In the first year, after thinning, apply the first fertilization: 500 kg of diluted human manure and urine per mu or 3-5 kg of urea, and in June-July apply 30 kg of ammonium phosphate as a top dressing. In the second and third years, after greening up, apply 40-50 kg of decomposed cake fertilizer, and before the rows close in late June apply 30-40 kg of granular ammonium phosphate fertilizer. When fertilizing, open furrows and apply into them, then cover with soil and water.

III. Harvesting and Processing

Harvest 2-3 years after planting. Generally, dig in late autumn after the stems and leaves wither, or after the spring thaw and before sprouting. Because the roots grow deep, dig deeply to prevent breaking the roots. After the roots are dug out, shake off the soil, cut off the stems and leaves, sun-dry until half dry, rub off the outer skin, and then quickly sun-dry or oven-dry. They can also be sliced and then sun-dried, but they must not be washed with water, nor sliced while fresh, otherwise the cut surface will turn green.

When drying in the sun, avoid exposure to strong light, because excessive exposure will make Scutellaria baicalensis turn red. At the same time, prevent it from being drenched by rain, because after rain the roots of Scutellaria baicalensis first turn green and then black, both of which affect quality. The finished product is considered best when it is solid, without holes, and bright yellow inside. Generally, 3-4 kg of fresh roots can be processed into 1 kg of dried product. The seed rate is about 2 kg per mu, and the yield of dried product is 200-300 kg per mu, with high yields reaching more than 380 kg.