How to Grow Licorice for High Yield? Detailed Explanation of Cultivation Techniques

Licorice, also known as sweet grass root, is a medicinal plant of the Fabaceae family. Its roots and rhizomes are used as medicine, and it has the effects of tonifying the spleen and boosting qi, clearing heat and detoxifying, moistening the lungs and stopping cough, and harmonizing various medicines. Licorice prefers a dry climate and tolerates severe cold. It is suitable for planting in sandy soil with deep soil layers, good drainage, a low groundwater table, and rich calcium content. The soil should preferably be neutral or slightly alkaline. Waterlogged lowlands, land with a high groundwater table, and acidic soil are not suitable for planting.

Licorice is generally propagated by rhizomes. After harvesting licorice in autumn or spring, use the thick roots for medicine, select thin rhizomes as seed material, and cut them into small sections of 10—15 cm, each with 2—3 buds. In autumn, plow the soil deeply to 30—50 cm, apply sufficient base fertilizer, with 2500 kg of manure and 200 kg of superphosphate per mu, then harrow level after plowing. Sow in the following spring around early April. Open furrows at a row spacing of 30 cm and a furrow depth of about 10 cm. Place the rhizomes flat in the furrows at a plant spacing of 10—15 cm, cover with soil, harrow level, firm and press down, water, and cover with plastic film. Concentrated seedling raising with scattered transplanting can also be used, with ridge cultivation and mulching with straw or plastic film.

Before and after emergence, licorice should be kept with constantly moist soil to facilitate emergence and seedling growth, and it should be watered promptly in dry weather. When the seedlings grow 2—3 true leaves, thinning should be carried out. After final thinning, the plant spacing should be 10—13 cm. Weeds should be removed promptly during the seedling stage. After the plants grow larger, rhizomes may be exposed above the ground, so soil should be banked up appropriately. Large clumps of grass can be pulled out, and hoeing is also suitable. In winter, 2000—2500 kg of farmyard manure can be applied per mu as a topdressing. After two years of cultivation, the rhizomes of licorice will already have spread throughout the entire plot, so no special management is needed.

Licorice has diseases such as rust, brown spot, and powdery mildew, as well as pests such as aphids and red spiders. For rust, use 0.30—0.40 degree lime sulfur mixture or 97% nabam at 400 times dilution for control; for brown spot, use 1:1:100—160 Bordeaux mixture or 70% thiophanate-methyl wettable powder at 1500—2000 times dilution for control; for powdery mildew, use 0.20—0.30 degree lime sulfur mixture for control; for aphids, use 50% fenitrothion at 1000—2000 times dilution or 40% dimethoate emulsifiable concentrate at 1500—2000 times dilution for control; for red spiders, spray with 20% dicofol at 1500—2000 times dilution or 25% chlordimeform aqueous solution at 500—1000 times dilution, once a week, for several consecutive times.

Licorice can be harvested 2—3 years after planting, from late September to early October, when the aboveground stems and leaves wither. Licorice roots are deep, so deep digging is necessary. They must not be broken by digging or have the root bark damaged. After digging out, remove the remaining stems and soil. Do not wash with water. While fresh, separate the main roots and lateral roots, sun-dry until half dry, tie into small bundles, then sun-dry until fully dry for medicinal use.