Orchids and fertilizers

The type, quantity and proportion of nutrients required by orchids are different from the whole developmental stages of germination, growth and flowering. Fertilization is to maximize the nutrients of orchid plants. If the fertilizer is not applied properly, the supply of certain nutrient elements is insufficient or excessive, and the proportion of various nutrients is out of proportion, which will affect the normal growth and development of orchid plants. In order to meet the requirements of various nutrient elements for plants, we must first understand the nutritional characteristics of orchids and the role of various nutrients, and apply fertilizers reasonably to regulate the nutrients needed in each growth period of orchids so as to achieve healthy growth. The essential nutrient elements for orchids are the same as other plants, mainly carbon, hydrogen, oxygen, nitrogen, phosphorus, potassium, calcium, magnesium, sulfur, iron, manganese, zinc, copper, boron, molybdenum, chlorine and other sixteen nutrient elements, which vary greatly. Such as carbon, hydrogen, oxygen, nitrogen, potassium, calcium, magnesium, sulfur and other elements are essential elements for orchid growth, and the demand is more, so it is called "a large number of nutrient elements." Manganese, boron, zinc, copper, molybdenum, iron, chlorine and other elements are also necessary for orchid growth, but the demand is very small, so they are called micronutrient elements. Most of the carbon, hydrogen and oxygen in these elements come from air and water. Calcium, magnesium, Ryukyu, iron and other trace elements are high in soil and are generally not deficient. If using artificial coarse plant material, in addition to supply nitrogen, phosphorus, potassium, but also need to supplement trace elements. Although orchids have different requirements for various nutrients, they are indispensable and irreplaceable. The three most needed are nitrogen, phosphorus and potassium, which are often called the three elements of fertilizer. In order to apply nitrogen, phosphorus and potassium reasonably, we must first understand their nutritional effects on orchids. To put it simply: nitrogen fertilizer can promote the formation of chlorophyll and protein, deepen leaf color and increase leaf surface, which is beneficial to photosynthesis. During the growing period, the application of nitrogen fertilizer can make the plant grow healthily. On the contrary, the nitrogen fertilizer is insufficient, the growth is weak, the plant is short, the chlorophyll content is decreased, and the photosynthesis is weakened, so the plant grows slowly and the leaves are thin and small. Of course, it should not be excessive, especially when the supply of phosphorus and potassium is insufficient, it will cause the leaves to grow too long, lodge easily, and be infected with diseases and insect pests, especially if used too much at one time, it will cause burning seedlings, so we must pay attention to reasonable application. Phosphate fertilizer can divide the cells of orchid plant, promote root respiration, increase nutrient absorption, provide energy for various metabolic functions, and is beneficial to growth and development. Sufficient phosphorus nutrition can directly participate in plant photosynthesis, accelerate the transport of photosynthate to the root, promote the development of root system, and be beneficial to flower bud differentiation and flowering. In particular, the application of phosphate fertilizer at seedling stage can promote root development and make root system grow early and develop quickly. It can also enhance resistance, drought resistance, cold resistance, disease and insect resistance and lodging resistance. It is also because phosphorus can maintain and regulate the metabolic process in the plant, such as when phosphorus is insufficient, the plant is short and the leaves are gray and lack of luster. The formation of new cells was weakened, the growth of buds and roots was inhibited, the flowering was late and the flowers were small. Excessive phosphorus can also have adverse effects, such as the increase of ineffective tillers of cereals, plant dwarfism, premature development of reproductive organs, premature senescence of plants and so on. Potassium fertilizer is an indispensable nutrient element for the growth and development of orchids, and participates in part of the metabolic process and regulation. Potassium is usually distributed in the areas with the most vigorous growth, such as buds, tender leaves, root tips, etc. When potassium fertilizer is sufficient, it can promote photosynthesis, promote the absorption of nitrogen and phosphorus, facilitate the formation of protein, enhance plant resistance to diseases and insect pests, lodging, drought and cold resistance. Under potassium deficiency, the metabolism of the plant was maladjusted, the photosynthesis was significantly decreased, the root growth was inhibited, the orchid leaves were thin and soft, the stress resistance was poor, and it was easy to be infected with diseases and insect pests. To understand the role of the above three elements, how to apply should be combined according to the different growth and development periods of various orchids. For example, Chunlan blossoms in Jiangsu and Zhejiang at the end of February and early March, and new buds grow from April to June. When the temperature rises above 15 degrees, nitrogen and phosphorus-based nutrients can be applied slightly at the beginning, which can promote early root growth, rapid development and rapid growth of new buds. After June, the orchid buds of some plants have been transformed into the new leaf growth period, when nitrogen fertilizer should be applied mainly to make the plants grow rapidly and make the orchid leaves wide and thick. September-October is the key, when the temperature difference between day and night is large, which is beneficial to the late growth of orchids, such as the application of average fertilizer of nitrogen, phosphorus and potassium in the early stage, it can promote the growth of orchid plants and sprout overwintering buds and make flower buds grow rapidly. In the later stage, the application of phosphorus and potassium fertilizer can not only make the pseudo-bulb plump plants mature, increase the germination rate and flowering rate next spring, but also enhance the cold resistance at low temperature and dormancy when the air temperature drops below 10 degrees. The best temperature for the growth of spring orchids is 18-28 degrees, when fertilization is easily absorbed. When the temperature is lower than 15 degrees or higher than 35 degrees, the orchid appears semi-dormant, and the fertilizer is not easy to absorb, so it is best not to apply fertilizer. In short, fertilizer is very important in daily cultivation, and should not be applied blindly. First, we should know the content of various nutrient elements and dilution times of fertilizer. Rather light and diligent, the application of the same concentration of fertilizer and water should be based on the strong state of orchid plants, such as weak orchid plants and fertilizer-intolerant varieties should be used with thinner fertilizer and water, appropriate application, in order to have a good effect, good orchids should not only be properly matched with nitrogen, phosphorus, potassium and other nutrients, but also be combined with the management of various links. In practice, only by exploring and analyzing step by step can we really understand the cultivation skills and experience of each link.