Key Points of Shaping and Pruning Techniques for Schisandra chinensis Cultivation
The vines of Schisandra chinensis are soft and cannot stand upright, so they need to attach to a support and twine upward to grow. Therefore, its shaping work includes two tasks: setting up supports and pruning.
(I) Setting up supports
The growth amount of Schisandra chinensis in the year of planting varies greatly. Under conditions of poor seedling quality and poor management, plant height generally reaches only 50-60 cm, but after stumping pruning, the average growth height in the second year can reach more than 150 cm, and by the third year it can cover the trellis surface. Therefore, supports can generally be set up in the spring of the second year (early to mid-May). Supports can use trellis poles and sun-resistant polyethylene rope. Bamboo poles are often chosen as trellis poles. Bamboo poles are 2.0-2.2 m long, with a top diameter of 1.5-2.0 cm; sun-resistant polyethylene rope with a thickness of 3×15 strands is more suitable, with the upper end fixed to the first iron wire at the top. According to the plant spacing, 1-2 poles per plant. When the plant spacing is less than 50 cm, one pole can be set per plant, placed about 5 cm beside the plant; when greater than 50 cm, two poles per plant, evenly inserted or fixed on both sides of the plant. The part of the bamboo pole entering the soil is best coated with asphalt to extend its service life. The trellis poles are fixed to the three trellis wires with thin iron wire. In a Schisandra chinensis orchard with good seedling quality and management, the plant can reach a growth height of about 2 m in the same year, so supports should be set up in late May of the planting year to facilitate rapid plant growth.
(II) Shaping
The purpose of shaping Schisandra chinensis is, through artificial intervention and induction, to make it grow and develop according to the grower's requirements, so as to fully use the trellis space, effectively use light energy, reasonably retain vines, regulate the relationship between vegetative growth and reproductive growth, and cultivate robust and long-lived plants, so that they adapt to climatic conditions and facilitate farming, pest and disease control, pruning, and harvesting operations, thereby achieving the goals of high yield, stable yield, and high quality.
The tree form commonly used for Schisandra chinensis is a training method with one group or two groups of main vines, that is, each plant retains 1 group or 2 groups of main vines, which are respectively twined on evenly arranged supports. On each support, 1-2 fixed main vines are retained. Lateral vines and fruiting mother branches grow on the main vines. The spacing between each fruiting mother branch is 15-20 cm, evenly distributed. Fruiting branches and vegetative branches grow on the fruiting mother branches, as shown in Figure 5-3. The advantages of this shaping method are that the tree structure is relatively simple, and the shaping and pruning techniques are easy to master; cultivation can be carried out between plants and rows, making weed control convenient; the plant volume and load are small, and the requirements for soil, fertilizer, and water conditions are less strict. However, because the plant is relatively upright, it is prone to forming a situation of strong upper growth and weak lower growth, with the fruiting position moving upward, so control needs to be strengthened.
Each tree generally needs 3 years to form its tree shape. During the shaping process, special attention should be paid to the selection and retention of main vines. Branches with strong growth vigor, full growth, and plump buds should be selected as main vines. The number of main vines in each group must be strictly controlled. Too many main vines will cause adverse consequences such as weakened tree vigor and chaotic retention of branch groups.