High-yield cultivation techniques of Rhubarb

Rheum officinale, alias general, fragrant rhubarb, horseshoe yellow, south rhubarb, etc., for polygonaceae perennial herbs. Underground rhizomes are used as medicine, which has the effects of purging heat, removing stasis, anti-bacterial and anti-inflammatory. Mainly produced in Qinghai, Gansu, Sichuan and other provinces, there are now introduced cultivation around.

1. Growth habits. Rhubarb likes cold, humid, cool climate, fear of high fever, avoid continuous cropping. With deep soil layer, loose fertile, rich in organic matter sandy soil is good.

2. Soil preparation and fertilization. Select high terrain, good drainage field, deep ploughing and careful cultivation. Combined with soil preparation, apply sufficient base fertilizer: 3000kg of miscellaneous fertilizer, 20kg of urea and 50kg of phosphorus and potassium fertilizer per mu. Then prepare the bed and wait for sowing.

3. Sowing. rhubarb seed propagation, sub-seedling and transplanting two steps. The sowing time is divided into spring sowing and autumn sowing. Spring sowing is around Qingming, autumn sowing is around the beginning of autumn, seeds are harvested and sown with maturity. Before sowing, first in the whole good ridge surface open into shallow ditch, and then seed evenly scattered into the ditch, soil watering to preserve moisture, in order to facilitate emergence. Sowing quantity per mu is 5kg. After sowing, seedlings can emerge at appropriate temperature for about 7 days. After the rhubarb seedlings are complete, strengthen management and transplant after one year of growth. When transplanting, rhubarb seedlings are planted on the finished bed surface according to the row spacing of 70- 50cm, and watered to preserve moisture for survival.

IV. Field management. After rhubarb seedlings, pay attention to intertill weeding to ensure that there are no weeds on the ridge surface. Dry weather timely watering, rainy weather pay attention to drainage. Topdressing should be applied once before and after the beginning of autumn; urea 20kg and potassium dihydrogen phosphate 10kg should be applied per mu. Rhubarb is easy to sprout and bloom 2-3 years after transplanting. In addition to seed plants, flowers and moss should be removed early to prevent nutrient consumption.

5. Pest control.① Root rot: 1:1:100 Bordeaux mixture can be used to control it before disease onset; or 65% mancozeb can be used to control it at the initial stage of disease. 2 downy mildew: usually in the early stage of the disease with ethyl phosphorus lead or carbendazim control. (3) Aphids are the main pests, which can be controlled by methamidophos. Underground pests were controlled with phoxim and carbofuran.

VI. Harvesting and processing. Rhubarb is generally harvested in the autumn of 3-4 years after planting and in time after seed maturity. When harvesting, first cut off the stems and leaves on the ground, then dig out the underground rhizomes, clean the soil, dry them and sell them as medicine.