High-Yield Cultivation Technique Tutorial for Bupleurum: Latest Cultivation Methods Explained

Bupleurum is one of the forty major medicinal herb varieties, with an annual demand of more than 3 million kg. It has the characteristics of high medicinal value, promising development prospects and stable market conditions. Wild Bupleurum resources are depleted, and because domestic cultivation requires a high level of technical expertise, it is difficult to meet market demand. Its price has consistently run at a high level, remaining between 20 and 30 yuan since 1996. The current market price is 28-32 yuan/kg. Bupleurum gives a return in the same year it is planted, with an average yield per mu of generally 150-200 kg, and a high yield of up to 300 kg over two years. Calculated at a market price of 30 yuan/kg, the benefit per mu is about 5,000 yuan. In addition, 15 kg of Bupleurum seed can be harvested, bringing the benefit per mu to more than 6,000 yuan. For planting Bupleurum, after deducting cumulative costs of 1,000 yuan for seed, work hours, labour, land and chemical fertiliser, the net profit is generally around 5,000 yuan, more than 10 times that of growing other food crops.

Cultivation Characteristics

Because of factors related to Bupleurum itself, planting in winter or early spring is preferable. The reasons are: (1) The lifespan of Bupleurum seed is relatively short. Scientific experiments have shown that after harvest, the germination rate of Bupleurum seed is 85% within 3 months and 50% within 6 months. As time goes on, the germination rate becomes lower and lower. (2) It has strict temperature requirements. The suitable period for Bupleurum germination is 10-20 degrees C; above 25 degrees C the germination rate of Bupleurum drops to 30%, at 30 degrees C the germination rate is 20%, and at 35 degrees C the germination rate is zero. (3) The seeds are small, and the seed surface has a layer of cuticle, so after being planted in the ground they generally only germinate after 20 days. (4) It is better to use the natural protection method. The so-called natural protection method means sowing in winter so that germination occurs in spring, using ground temperature to provide constant-temperature natural protection. The effect is especially good and there is no need to cover with straw.

Field Selection and Land Preparation

Bupleurum is cold-resistant and drought-resistant, but avoids waterlogging. For the field, choose sandy loam soil with deep, fertile soil layers, loose texture and good drainage and irrigation. Before sowing Bupleurum, plough the soil deeply, level it and harrow it fine. In conjunction with land preparation, apply 2,000-3,000 kg of decomposed farmyard manure per mu, 10-15 kg of diammonium phosphate, or 20-30 kg of phosphorus-potassium compound fertiliser.

Cultivation Techniques

Bupleurum is mainly propagated by seed, and can generally be sown in winter or spring, but winter sowing is preferable because seedlings emerge earlier and more uniformly in early spring. Winter sowing should be carried out from November to early December, with a seeding rate of 3-4 kg per mu. Seed treatment must be done before sowing. Bupleurum seeds are tiny, and the seed surface has a layer of cuticle. Generally, the cuticle must degrade after sowing before seedlings can emerge, which often easily affects normal and timely emergence, resulting in uneven and incomplete seedlings. After the seeds are carefully selected, they can be soaked in warm water with an appropriate amount of washing powder added, gently rubbed and washed, then rinsed clean of washing powder with clean water and dried for storage in preparation for sowing. When sowing, an appropriate amount of fine loess and plant ash can be used to mix the seeds evenly before broadcasting. The sowing methods can be either drilling in furrows or broadcasting. For furrow sowing, fertiliser can first be placed into the furrow; when broadcasting the seeds, the covering soil should not be too thick, and the soil must not exceed 0.5 cun in thickness. For broadcasting, the mixed seeds can be evenly scattered over the surface of the field on well-levelled flat ground, and after sowing a shallow covering can be made by hand. Where conditions permit, the sown field can be irrigated to settle the soil and appropriately compacted. Seedlings can emerge after spring. The spring sowing method is the same as winter sowing, but grass must be covered to retain moisture.

Field Management

After seedlings have emerged completely, combine fertilisation with one shallow loosening of the soil. When the seedlings are about 1-2 cun tall, thin them in conjunction with weeding, removing overly dense, small and weak seedlings. Leave plants at a spacing of 1-2 cun between plants and 5-6 cun between rows. At the tillering stage, topdress with 20 kg of superphosphate and 10-15 kg of ammonium sulphate, opening furrows between the rows for the topdressing and then covering firmly with soil. At the flowering and budding stage, spray 4-5 kg of potassium dihydrogen phosphate for foliar topdressing to promote fruit setting and seed filling. During excessive rainy and overcast weather, promptly clear ditches to drain water and prevent waterlogging, so as to reduce field humidity and prevent root rot. Throughout the growing period, pay attention to disease and pest damage. For insect pests, the main control target is generally soil-dwelling pests. Shachongdan or shachongshuang powder can be used at 100-200 g per mu, mixed evenly with soil and scattered in the field at sowing time to prevent cutworms, grubs, wireworms and other soil-dwelling pests. For pests occurring during the growing period, such as aphids and leaf green caterpillars, 90% trichlorfon or 40% omethoate emulsifiable concentrate at 200 times dilution, as well as pesticides such as deltamethrin and kuaishaling, can be sprayed for control.

Harvesting and Processing

Collection of Bupleurum stems, seeds and medicinal roots. For collecting stems and seeds, when the seeds turn yellow-black and the leaves have all withered and yellowed, the stems can be cut together with the seeds and threshed. Dry the stems and seeds separately in the sun and store them properly for later sale. The medicinal roots should generally be harvested after two years. For harvesting the medicinal roots, deep digging by hand can be used to dig out all the medicinal roots. They must not be pulled out directly, to prevent broken roots from affecting yield and to increase income. The medicinal roots should be sorted by category, uniform and neat in size, tied into small bundles, and dried in the sun before sale.