Cultivation techniques of licorice

Licorice, also known as sweet grass and sweet root, has the effects of reconciling medicinal properties, reducing or alleviating drug toxicity and moistening the lungs. at the same time, it also has the characteristics of cold resistance, heat resistance, drought tolerance, fear of waterlogging and light, so it is an excellent plant for preventing wind and fixing sand. The cultivation techniques are as follows:

Land preparation is suitable for selecting sandy soil with deep soil layer, deep groundwater table and good drainage, and the soil salt content should not exceed 0.2%. It is not suitable to plant in rainy or sticky soil with poor drainage, because the root is easy to rot or the main root is short. there are more branched roots and hairy roots, and the economic value is not high. It is best to choose a flat and watery place for raising seedlings. Transplanting land is available for cultivated land, barren slope and barren beach. Before soil preparation, base fertilizer is applied first, mainly organic fertilizer, 15000 ~ 45000 kg of rotten barnyard manure, 300 kg of diammonium phosphate or calcium superphosphate per hectare, and then ploughed deeply about 25 cm, and then leveled according to the topography. The nursery land had better be formed into a flat bed so as to facilitate irrigation.

Propagation and transplanting licorice is propagated with seeds, but the seed coat is hard and impervious, so it is difficult to germinate, so it must be treated before sowing. The method of crushing with a rice mill has the best effect, and the germination rate can reach 95% in general. The method to check whether the treatment is qualified is to soak the crushed seeds in a small amount of water for 2 to 4 hours. If most of the seeds are soaked, the treatment is qualified. If they are not qualified, they can be crushed again. If the seed coat has been broken, the seeds will not germinate. In addition, harvest tender full seeds, the germination rate can reach 95%, should be harvested when the pods are green and purplish red, dry and thresh to remove impurities and shrunken seeds, leaving light brown full seeds to sow. The seeds can be sowed from late April to mid-August, but May is the best, and places without irrigation conditions should be sown in the rainy season. When sowing, it should be planted in trenches with a spacing of 20cm and 25cm, and the amount of seeds used per hectare is 30kg. Shallow sowing can be about 1 cm in places with irrigation conditions, and deep sowing can be about 2 cm in dry areas without irrigation conditions. Watering in time after sowing, keeping the topsoil moist before emergence, and gradually reducing the watering times with the growth of seedlings. Weeding should be regularly ploughed in the seedling stage. When the seedlings grow to 10-15 cm, one nitrogen fertilizer, such as urea or ammonium nitrate, can be applied 120-150 kg per hectare. Generally, it can be transplanted in the second year in spring and in the third year in spring sown after autumn. The transplanting period usually occurs after the surface is thawed in early spring to before emergence. When transplanting, dig up the roots and seedlings, cut off the roots, leave the root tips 40-50 cm long, separate the thickness, and plant them respectively. When transplanting, dig a ditch with a depth of 10 cm and 15 cm according to the row spacing of 40 cm and 50 cm, and put it in the trench according to the plant spacing of 15 cm and 20 cm.

After field management, pay attention to ploughing and weeding and watering in time. Attention should be paid to topdressing during the growing period. according to the plant growth, topdressing was applied twice a year, the first time after emergence from April to May, and the second time in the peak growth period from June to July, 20 kilograms of diammonium phosphate was applied each time, ditching and deep application beside the root, covering the soil and watering after application.

Disease and pest control rust at the initial stage of the disease with 25% powder wettable powder 1000 times liquid spray control, once every 7 to 10 days, a total of 2 spray 3 times. Powdery mildew was sprayed with 1000 times of methyl topiramate wettable powder and sprayed for 3 times according to the severity of the disease. Licorice seed wasps were sprayed with 1000 times of dimethoate EC. Aphids were sprayed with 40% dimethoate EC 1000-2000 times, once every 10-15 days, 2 times in a row.