Detailed Explanation of Cultivation Techniques and Field Management Key Points for Medicinal Tree Peony

Tree peony is a plant of the genus Paeonia in the family Paeoniaceae. Because of its large, brightly colored flowers and rich fragrance, it has the reputation of "king of flowers"; at the same time, the root bark of tree peony can also be used as medicine, with the effects of clearing heat and cooling blood, dispersing blood stasis and unblocking menstruation, and is used for heat-induced diseases, hematemesis, bruises and injuries, etc. Ornamental tree peonies are most famous in Luoyang, Henan and Heze, Shandong. Medicinal tree peonies are most effective when using the "Fengdan" from Tongling, Anhui. I. Biological Characteristics Tree peony prefers a cool climate, is relatively cold-tolerant, and not tolerant of damp heat; it is drought-tolerant and not tolerant of waterlogging. Whether on flat land or sloping land, it can be planted as long as the soil is fertile, the soil layer is deep, and the soil texture is loose neutral or slightly acidic sandy loam. Strongly acidic soil, saline-alkali land, clay, low-lying wet land, and shaded areas under trees are not suitable for planting. II. Cultivation Techniques for Medicinal Tree Peony 1. Site Selection and Land Preparation Medicinal tree peony is a root-type plant, so land with sufficient sunlight, high terrain, and good drainage should be selected for planting; both flat land and sloping land are suitable. The previous crop is preferably corn, cotton, etc. After the previous crop is harvested, deep plowing and land preparation should be carried out, generally to a depth of 50-80 cm, and 3000-5000 kg of base fertilizer per 667 sq m (1 mu), plus 50 kg each of phosphorus and potassium fertilizer. After drying the land for 8-10 days, fine plowing should be carried out to a depth of 50-60 cm, then the land should be leveled and made into high beds. The beds should be shaped like a turtle shell to facilitate drainage, with a bed width of 1.5-2.0 m, a ditch depth of 30 cm, and a ditch width of 40 cm. 2. Sowing Sowing can be carried out from late August to mid-November, with mid-September to late September being the best sowing period. When sowing, seeds that are plump, black, glossy, and free of pests and diseases should be selected. Before sowing, first soak the seeds in warm water at 45°C for 24 hours, then drain and air-dry them until sowing. At present, hole sowing or drill sowing is generally used, and the width of the seedling bed is preferably 1.2-2 m. Hole sowing: In medicinal material production areas, holes are generally dug at a row spacing of 30 cm and a plant spacing of 20 cm. The holes are arranged in a triangular pattern, with a depth of about 10 cm and a diameter of about 5 cm. The bottom of the hole is flat. An appropriate amount of base fertilizer is applied to each hole (chemical fertilizer cannot be used), then about 3 cm of fine soil is covered over it and compacted and leveled. Generally, 20 seeds are sown per hole, and they should be evenly distributed within the hole. The seed rate is about 150 kg per 667 sq m. Drill sowing: In medicinal material production areas, sowing furrows are generally opened transversely at a row spacing of 25 cm and a sowing width of 10-20 cm, with a depth of 6 cm, and the seeds are evenly sown into the furrows. The seed rate is about 100 kg per 667 sq m. After hole sowing or drill sowing, the soil should be closed immediately, and after the bed surface is leveled, thatch should be added as a cover. Seedlings can emerge from late February to early March of the following year. Before emergence, the cover grass should be removed in time. If drought occurs, water should be applied in time. After two years, they can be transplanted and established. 3. Field Management of Medicinal Tree Peony Transplanting and establishment: Generally, after leaf fall in autumn (September-October), 2-year-old seedlings are dug up for transplanting. Dig pits at a row spacing and plant spacing of 50 cm x 30 cm and a depth of 20-30 cm, and plant 1 strong seedling or 2-3 thin seedlings per pit. When filling with soil, keep the root system straight. When the soil is filled to half, gently lift the seedling upward by hand, then continue to cover with soil and compact it, so that the roots spread out and are in close contact with the soil. After planting, water thoroughly to settle the roots. Intertillage and weeding: Start intertillage and weeding after sprouting in the spring of the second year after transplanting. Carry out intertillage 3-4 times each year to keep the field free of weeds and the soil loose. Generally, earthing up should be carried out together with intertillage and weeding. Exposing the roots: During April-May, choose sunny days, remove the covering, and dig away the soil around the root zone to expose the root crown and let it receive light. After 2-3 days, combine intertillage and weeding with earthing up and fertilization. Topdressing: Tree peony likes fertilizer. Apply fertilizer once each at the beginning of spring when the soil thaws, after flowering, and before the onset of winter. Apply 150-200 kg of decomposed cake fertilizer per 667 sq m. Fertilization is generally carried out together with earthing up. Drainage and irrigation: If drought occurs during the growing period, water in the morning or evening. In the rainy season, clear the ditches and drain water in time to prevent waterlogging and root rot. Bud removal and pruning: Except for plants retained for seed production, flower buds should be removed in time after budding in spring. Bud removal should be done on sunny days after the dew has dried to prevent wound infection and disease. From October to November, cut off dead branches and excessive vegetative branches, remove fallen leaves, and burn them in a centralized manner. III. Harvesting and Processing of Medicinal Tree Peony Harvesting: Harvesting can be done 3-5 years after planting, with 4-year-old plants being best. It is generally harvested in October, when both quality and yield are relatively high. Harvesting should be carried out on sunny days, and the range of soil removal should be larger, so that the whole plant is dug up intact; be sure not to break or snap the roots, as this affects quality. After digging, shake off the soil, cut off the fresh roots, and pile them in a cool place for 1-2 days. After they lose some water and become soft, process them. Processing: First remove the fibrous roots from the tree peony roots and dry them in the sun to obtain Danxu. Twist and crack the root bark, pull out the woody core, and obtain Danpi. For root bark with thicker root strips and relatively abundant powdery content, scrape off the outer cork with a bamboo strip and dry it in the sun to obtain Guadanpi, also called Fendanpi; for root bark with thinner root strips and relatively poor powdery content, do not scrape off the outer skin and directly dry it in the sun to obtain Liandanpi, also called Liandan. According to the thickness of the roots and the degree of powdery content, spread them out separately for drying, storage, and packaging.