What kind of environmental conditions does winter jujube cultivation require?
Winter jujube is a fruit of the Rhamnaceae family. It usually ripens in October in winter, which is why it is called winter jujube. It contains extremely rich vitamin C, the most abundant among all fruits, surpassing even the vitamin C-rich fruit hawthorn. Although it ripens in winter, it is extremely sensitive to the environment it needs for growth. So what exactly are the requirements of winter jujube for the surrounding growing environment? Let's take a look below!
1. Temperature
Temperature is one of the important factors for the normal growth and development of all crops, and winter jujube is no exception. The temperature factor directly affects the distribution of winter jujube. It is a temperature-loving fruit. Although it ripens in winter, it is sown in spring, and the growth process also requires relatively high temperatures. It sprouts relatively late and sheds its leaves very early. After sowing in spring, when the temperature rises back to about 14°C, the seeds will begin to germinate, and at 17°C they begin to shoot branches and differentiate buds. At about 20°C, flower buds begin to appear, and at 25°C they enter the full bloom stage. It has a strong ability to adapt to temperature and can safely overwinter at minus 30°C in winter, and can also withstand high temperatures of 45°C and grow normally.
2. Humidity
Winter jujube is relatively resistant to waterlogging and drought, and it can grow and develop normally in areas with relatively high annual rainfall. Even if the orchard accumulates water for 0.5-1 month, it will not die from waterlogging. However, winter jujube still has certain humidity requirements at different growth stages. During the flowering and pollination-fertilization stage, the water demand is relatively large, and the relative humidity requirement is about 75%. If the humidity at this stage is lower than 40, it will affect pollen germination and pollination-fertilization, leading to flower and fruit drop and reduced yield. Conversely, if continuous rainy weather occurs during the flowering period, it will also cause pollen not to germinate and to absorb water and rupture, affecting the fruit-setting rate. Soil moisture directly affects the nutrient balance in the tree.
3. Light
Jujube trees rely on photosynthesis to maintain their own growth and development, and light energy is the root of the growth of the entire winter jujube tree. Its light-loving nature is very strong, and the intensity of photosynthesis is directly proportional to the light received by the tree and the length of sunlight. Reasonable light duration promotes cell differentiation and controls cell division, which is greatly beneficial to nutrient accumulation and growth of the tree. The fruit-setting rate is also directly proportional to the length of light duration. Insufficient light will not only reduce the fruit-setting rate, but also affect the development of the tree roots. Poor root development will make it impossible to supply the water and nutrients needed by the tree in time.
4. Soil
Soil is an important medium for supplying the nutrients and water needed by jujube trees. The fertility, permeability, and pH of the soil all directly affect the development of jujube trees. Although winter jujube does not have strict soil requirements, it can also grow in saline-alkali and barren soils. However, in more fertile soil, winter jujube trees grow tall, with deep and extensive roots, a robust tree body, and high and stable yields. If the soil is too barren, with a lot of clay, poor water and fertilizer retention, and extremely poor soil permeability, it will lead to poor development of the jujube tree, small and dry fruit, and reduced yield.
Although winter jujube ripens in winter, this does not mean that its environment can be arbitrary and still achieve high yield, because from sowing to ripening, winter jujube needs nearly a year. Therefore, sowing is carried out in spring, and correspondingly the surrounding environment also has certain requirements. The environment and nutrients needed by winter jujube must be ensured, so as to achieve the goal of high yield.