The Latest Tutorial on Seedling Raising and Transplanting Techniques for Licorice Cultivation

In licorice cultivation there are three propagation methods: direct seeding, seedling raising and transplanting, and rhizome propagation. By comparison, direct seeding gives a lower yield and a larger proportion of rhizomes; seedling raising and transplanting gives a high yield but poorer quality; rhizome propagation gives a high yield and a large proportion of root strips, is much in demand on the market, and is mostly used in production. This cultivation method is described below.

Site selection and land preparation

Choose a sandy loam with deep, loose, fertile soil. After the site is chosen, apply 3000 kg of farmyard manure, 50 kg of superphosphate and 20 kg of potassium sulfate per mu as base fertilizer; the ploughing depth must reach more than 40 cm. Level and harrow the soil fine, and make flat beds 110 cm wide.

Selecting seed rhizomes

When harvesting licorice in February, select straight, thick rhizomes with short internodes and adventitious roots at the nodes as seed rhizomes. Cut the selected rhizomes into small sections 15 cm long, so that each section has at least three bud-bearing nodes. Soak the cut rhizomes in a 30 ppm gibberellin solution for 3 to 5 minutes, then plant them immediately.

Planting

On the prepared bed surface, open three small furrows 15 to 18 cm wide and 5 to 7 cm deep along the direction of the bed ridge. Place two rows of seed rhizomes in each furrow, end to end, spray with an 800-fold phorate solution, then cover with soil so that the seed rhizomes lie 4 to 5 cm below the bed surface. Tread firmly with the foot, water thoroughly once, and when the bed surface no longer sticks to the foot, hoe lightly to conserve moisture and raise the soil temperature.

Field management

Licorice propagated from rhizomes emerges slowly; at a soil temperature of 18°C it takes about 20 days to reach 80% emergence. Therefore, during this period be sure to do a good job of drought resistance and moisture conservation, keeping the bed surface moist to favour emergence. Seed rhizomes forced with gibberellin produce slender seedlings after emergence; spray with daminozide or chlormequat as directed to make them thick and sturdy. After full emergence, broadcast 15 kg of urea per mu and spray 30 to 60 kg of a 0.3% potassium dihydrogen phosphate solution. Thereafter, hoe frequently to clear weeds and actively control underground pests to ensure full and vigorous seedlings.

Pest and disease control

In licorice production, the most common insect pests are cutworms and wireworms, and the most common disease is powdery mildew; the two are the main causes of yield reduction. The control methods have been described above and are emphasized here so that attention is paid to them. Other pests and diseases can be controlled according to symptoms.

Harvesting and processing

Harvest can be done from the Autumn Equinox of the second year after planting until before spring sprouting in the third year. Dig up starting from one end of the bed, take out the root strips intact, dig out all the rhizomes, cut off the stems and leaves, shake off the soil and sun-dry; after drying, tie into bundles and they are ready for sale. The roots and rhizomes can also be tied separately and sold separately. Good licorice as a commercial product is dry, free of impurities and full of powder.