Medicinal plant licorice cultivation technology

● Growth Habits

Licorice, also known as sweet root, red licorice, or grass, is a leguminous plant used for its root and rhizome in traditional medicine. It has detoxifying properties, helps soothe the lungs and relieve coughs, strengthens the spleen’s qi, and harmonizes other medicinal ingredients. Licorice thrives in temperate regions, particularly in plains, mountainous areas, or river valleys at elevations between 0 and 200 meters. It prefers sandy soils with a neutral to slightly alkaline pH. Licorice requires ample sunlight and a significant temperature difference between day and night. In China, it is commonly cultivated in the northwest, north, and northeast regions due to their suitable climatic conditions.

● Field Management

1. When planting, maintain a spacing of about 30 cm between rows, and keep the distance between individual plants between 18.5 cm and 20 cm to ensure proper growth.

2. Watering is crucial during the early stages after sowing to keep the soil consistently moist, which supports seed germination and seedling development. The irrigation schedule should be adjusted based on soil type and salinity: for sandy, non-alkaline or slightly saline soils, watering can be done after sowing; for clayey or highly saline soils, watering should be done before sowing to protect the young plants. Once the plants are well established, further irrigation is generally unnecessary.

3. Weeding is typically carried out in the first year, especially during the seedling stage, to prevent competition from weeds. From the second year onward, licorice roots grow vigorously, making it difficult for weeds to compete, so weeding becomes less necessary.

4. Apply sufficient base fertilizer before sowing. In the spring, phosphorus-based fertilizers can be applied, and organic manure can be added before each mu (a Chinese unit of area) in winter. Since licorice has nitrogen-fixing nodules, it usually does not require additional nitrogen fertilizers.

5. Disease and pest control is important, especially during the rainy season when powdery mildew and rust may occur, and during dry periods when spider mites are common. These can be managed using 40% Dimethoate EC diluted 1000–1500 times.

● Harvesting and Processing

The roots of licorice grow deep underground, so careful digging is essential to avoid damage. After harvesting, remove the stems and excess soil, but do not wash the roots with water. Fresh main and lateral roots should be separated, and the fibrous parts, hairs, and branches should be removed. Dry the roots thoroughly, bundle them into small groups, and continue drying until fully dehydrated. Alternatively, licorice can be harvested in early spring before the leaves and stems appear, but the quality of roots harvested in autumn is generally superior.