Detailed Explanation of Key Techniques for Licorice Seedling Raising and Transplanting

Licorice is a perennial herbaceous plant of the Fabaceae family, also known as sweet herb, and is widely used medicinally.

I. Morphological Characteristics: Plant height 50-120 cm. The root is thick and large, cylindrical, reddish-brown, with horizontal rhizomes. The stem is upright, with pinnate compound leaves, alternate, 5-17 leaflets, ovate or elliptical; flowers are papilionaceous, light purplish-red. The pod is curved, sickle-shaped, with external bristles. Seeds are round, brownish-green, with a 1000-seed weight of 11.93 grams. Flowering period is July-August, and fruiting period is August-October.

II. Growth Characteristics: Licorice is mainly distributed in the "Three North" regions of China. It has low requirements for soil and prefers weakly alkaline sandy land, grasslands, riverbanks and desert areas. When introduced to the black soil of grain-producing areas, it grows vigorously with high quality and high yield.

III. Seedling Raising Techniques: First raise seedlings in a nursery for 1 year, then transplant the seedlings into the field in the autumn of the same year or the following spring. Raising seedlings on 1 mu of land can transplant 5-7 mu of land.

1. Land Selection and Fertilization: Licorice is a deep-rooted plant, so land with fertile soil, loose texture, good drainage and rich organic matter should be selected for planting. Deep plow 40 cm, and at the same time apply 20 kg of diammonium per mu as base fertilizer, then form ridges 65 cm wide, and press down and wait for sowing.

2. Sowing Time: Licorice can be sown in spring, summer and autumn. Spring sowing is from Qingming to Guyu, summer sowing is from Lixia to Xiaoman, and autumn sowing is carried out before the ground freezes, with seedlings emerging the following spring.

3. Sowing Method: On the ridge surface, use a plow to open a 20 cm wide furrow, attach a roller after the plow to press it flat, tread the grid manually, and use a seed gourd to evenly scatter the chemically treated seeds on the ridge surface, cover with about 2 cm of soil, and then press down. The sowing rate is 5-8 kg per mu. With good soil moisture, full seedlings can emerge in about 10 days.

IV. Seedling Stage Management: After licorice seedlings emerge, frequently check whether there is a small amount of seedling death. If so, spray 100 g of thiophanate-methyl plus 0.25 kg of urea per mu, add 50 kg of water, fully dissolve, and spray on the seedling leaves, which can effectively prevent licorice seedling death. If missing plants or broken rows are found, reseed and replant promptly to ensure full seedlings in the field.

When licorice has grown 4-6 true leaves, apply urea once along the furrow in combination with intertillage, 10 kg per mu. At 10 leaves, as the temperature rises, field weeds begin to grow vigorously, so hoe and cultivate frequently, generally 3 times. When weeds are severe, spray 150-200 g of sethoxydim per mu, which can effectively kill grass weeds; the remaining broadleaf weeds can be removed manually, thus ensuring no weeds in the field. Do not thin seedlings in the nursery land; raise 100,000-120,000 seedlings per mu.

When licorice has 15 true leaves, cotton bollworm and aphids may occur. Use 100-200 g of methamidophos per mu for foliar spraying; for aphids, 100 g of omethoate can be used. When both pests occur at the same time, the two pesticides can be mixed and sprayed. After licorice closes its rows, pay attention to pulling out large weeds in the field early, and drain field water promptly during the rainy season to prevent root rot.

V. Field Transplanting: Transplanting in the autumn of the same year yields slightly higher output than transplanting the following spring. When transplanting, the dug roots should retain a 5 cm stubble above the root crown and horizontal stems, and should be planted while being dug; it is best not to heel in temporarily. It is absolutely not allowed to cut off the overwintering buds and fibrous roots of the root crown. Use a plow to open a 10 cm deep furrow, place the licorice roots obliquely or flatly in the furrow, with a plant spacing of 10 cm, cover with 10 cm of soil, and press down to preserve soil moisture. Plant 18,000-20,000 plants per mu; if conditions permit, water once to settle the roots before the freeze. A series of field management measures before and after transplanting, such as land preparation, fertilization and pesticide application, are the same as for seedling raising. Spring planting is around Qingming, and autumn planting is carried out after the autumn harvest is completed.

VI. Harvesting and Processing: Licorice can be harvested in the autumn of the second year after transplanting, generally yielding 800-1000 kg of dry goods per mu. In October, lift and harvest with a plow, remove the soil, tie into small bundles according to different grades such as main root, lateral root and branch root, and dry in the sun for sale; it can also be harvested before germination the following year.