What are the general characteristics of fertilizing Schisandra chinensis?

Schisandra chinensis differs from field crops or vegetable crops in that it is a perennial climbing vine with a long growth cycle. Throughout its entire life cycle, all types of seedlings go through the processes of growth, fruiting, renewal and aging. In its annual cycle, there are different phenological stages such as sprouting, shoot extension, flowering, fruiting, ripening and dormancy. In different growth and development stages, the nutritional characteristics of the various seedlings differ, but compared with field crops or vegetable crops, Schisandra chinensis has the following nutritional characteristics:

(1) Large amount of nutrients absorbed. In order to meet the needs of the growth and development of its aboveground and underground parts and to provide a large amount of fruit year after year, the seedlings must absorb a large amount of nutrients from the soil every year, and the absorption by mature seedlings is even greater.

(2) Continuous consumption of nutrients. Schisandra chinensis has a long growth cycle, and generally the same plant continues to grow on the same plot for more than ten years. Because Schisandra chinensis is fixed in position and continuously absorbs nutrients, certain nutrient elements in the soil are often excessively depleted. Therefore, timely supplementation through fertilization is necessary. Otherwise, deficiencies of certain trace elements (such as iron, boron and zinc) will occur and affect fruit yield and quality. Schisandra chinensis orchards should be given appropriate applications of large amounts of biological organic fertilizer, suited to the specific soil's agrochemical characteristics and the trace element requirements of Schisandra chinensis seedlings.

(3) Need to store nutrients before winter. In the roots, branches and trunks of Schisandra chinensis seedlings, large amounts of nutrients are stored, including not only carbohydrates but also nitrogen-containing compounds and various mineral elements. Sprouting, flowering and growth in early spring mainly consume the nutrients stored in the plant. Therefore, after fruit harvest and before leaf fall, basal fertilizer should generally be applied early, mainly organic fertilizer, supplemented with some nitrogen, phosphorus and potassium chemical fertilizers, so that the rich nutrients stored in the plant can be used in early spring of the following year, which plays a certain role in increasing the flowering and fruit-setting rates, promoting robust shoot growth, enlarging the fruit and increasing yield. Early application of basal fertilizer also helps overcome the alternate bearing phenomenon of fruit trees.

(4) Strong ability to absorb nutrients from deep layers. This characteristic must be noted when fertilizing seedlings. At the same time, the seedling root system is not well developed, and the horizontal rhizome has a strong longitudinal ability to absorb nutrients, making its adaptability to external environmental conditions stronger than that of field crops or vegetable crops. Especially for mature seedlings, certain nutrients can be absorbed from the lower soil layers to supplement the deficiency of nutrients in the upper soil layers. When fertilizing fruit trees, one should consider not only the surface soil but also the soil nutrient status of the layer where the root system is densely distributed, and apply fertilizer to a certain depth, so as to facilitate the fertilizer-seeking growth and rooting of the Schisandra chinensis root system, benefit root absorption, and improve fertilizer use efficiency and the efficiency of survival and yield increase.

(5) Annual cycle nutritional characteristics. The seedling is a perennial crop, and its annual cycle nutritional characteristics are: in the early growth stage (sprouting, flowering and the rapid growth period of branches and leaves), nitrogen requirement is highest, after which the requirement begins to decline, and a certain amount of nitrogen is still needed after fruit harvest; phosphorus content increases somewhat during the growth period, but the requirement changes little until the later stage; potassium content is relatively high in the early growth stage, and potassium uptake peaks in the middle growth stage.