Detailed Explanation of Key Techniques for Licorice Seedling Raising and Transplanting
Licorice (Glycyrrhiza) is a perennial herbaceous plant of the Fabaceae family, also known as sweet grass, 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 erect, with pinnately compound leaves arranged alternately, 5-17 leaflets, ovate or elliptical; flowers are papilionaceous, pale 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. The flowering period is July-August, and the fruiting period is August-October.
II. Growth Characteristics: Licorice is mainly distributed in the "Three Norths" region of China. It has low soil requirements and prefers weakly alkaline sandy land, grasslands, riverbanks and desert areas. When introduced to the black soil of grain-producing regions, 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 phosphate per mu as base fertilizer, then form ridges 65 cm wide, press and wait for sowing.
2. Sowing Time: Licorice can be sown in spring, summer or autumn. Spring sowing runs from Qingming to Guyu, summer sowing 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 point gourd to evenly scatter the chemically treated seeds on the ridge surface, cover with about 2 cm of soil, then press immediately. The sowing rate is 5-8 kg per mu; with good soil moisture, full seedlings can emerge in about ten days.
IV. Seedling Stage Management: After licorice seedlings emerge, frequently inspect them for any small number of dead seedlings. If any are found, spray 100 g of thiophanate-methyl plus 0.25 kg of urea per mu, add 50 kg of water, dissolve fully, and spray onto the seedling leaves; this can effectively stop licorice seedling death. If missing seedlings or broken rows are found, replant and fill in promptly to ensure full seedlings in the field.
When licorice has grown 4-6 true leaves, apply a topdressing of urea once along the furrows in combination with intertillage, 10 kg per mu. At 10 leaves, as temperatures rise, 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-family weeds; the remaining broadleaf weeds can be removed by hand, ensuring no weeds in the field. The seedling bed is not thinned, yielding 100,000-120,000 seedlings per mu.
When licorice has 15 true leaves, caterpillars 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 insects occur at the same time, the two agents can be mixed and sprayed. After licorice closes its rows, pay attention to pulling out large weeds 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 gives a somewhat higher yield than transplanting the following spring. When transplanting, leave 5 cm of stubble and horizontal stems above the root crown of the dug-out roots, and plant while digging; it is best not to heel in temporarily. It is absolutely not permitted 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 flat in the furrow, with a plant spacing of 10 cm, cover with 10 cm of soil, and press to preserve moisture. Plant 18,000-20,000 plants per mu; if conditions permit, water once before freezing to settle the roots. 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 finished.
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 it out with a plow, remove the soil, tie it into small bundles according to different grades such as main root, lateral root and branches, and dry it in the sun for sale; it can also be harvested before sprouting the following year.