How to apply chemical fertilizers for the best effect

How to apply chemical fertilizers How to apply chemical fertilizers Plants first need to absorb large amounts of the major nutrient elements - carbon, hydrogen, oxygen, nitrogen, potassium, calcium, magnesium, phosphorus and sulfur - from the air, soil and water. In the dry matter of higher plants, each of these elements accounts for more than one thousandth. Then they need to absorb the trace nutrient elements - chlorine, iron, manganese, boron, zinc, copper and molybdenum - from the soil. These elements account for only a few ten-thousandths or less of the dry matter. If any one of these sixteen nutrient elements is lacking, higher plants cannot grow normally, so they are called the essential nutrient elements for the growth of higher plants. These nutrient elements make up the structural and life substances of the plant body, such as cellulose, lignin, protein, nucleic acid, fat, chlorophyll and enzymes. Some of them also serve as catalysts of metabolism within the plant, while others have special functions such as regulating cell permeability. In the plant body, the essential nutrient elements are equally important regardless of quantity, and the special function of any one nutrient element cannot be replaced by other elements. This is the law of equal importance and the law of non-substitutability of nutrient elements. In actual practice, we apply the three fertilizers nitrogen, phosphorus and potassium the most, because plants have a relatively large demand for nitrogen, phosphorus and potassium, while the available nutrient supply in the soil is insufficient; the demand for calcium, magnesium and sulfur is likewise relatively large, but the content of available calcium, magnesium and sulfur in the soil is relatively high, so generally no supplement is needed. The trace nutrient elements in some soils are also relatively deficient, so we also apply trace element fertilizers. We who growflowersoften have experience in this regard: a fertilized potted flower grows much faster than an unfertilized one, because the potflower'savailable nutrients are easily lost with frequent watering, and after fertilizing the nutrients are replenished, so the potted flower can grow normally. This is true for growing flowers, and growingorchidsis no exception.Orchidfertilization should first of all be balanced fertilization, that is, according to the nutrient status of the soil, rationally apply nitrogen, phosphorus, potassium and various trace element fertilizers. When growing orchids at home, we generally do not know the nutrient status of the growing medium, so we can only judge by the condition of the seedlings. Now there is another problem in growingorchids: the growing medium is increasingly tending toward being soilless, and the nutrients contained in the growing medium are very limited, so the application of various nutrients becomes indispensable. Fertilization methods include basal application and topdressing. Foliar spraying is also a method of topdressing. For basal application there is now a relatively good type of fertilizer - coated fertilizer. Coated fertilizer uses resin, polyethylene and other substances with permeation ability to coat the surface of the fertilizer. Applied to the soil, it can regulate the release of nutrients according to the concentration of nutrient ions in the soil, so the soil has nutrients but the concentration is not so high as to cause fertilizer damage to orchids, and the fertilizer effect lasts as long as half a year. As a basal fertilizer, the nitrogen content should be a bit higher, and there should also be some phosphorus and potassium; if it also contains trace elements, so much the better. Two kinds are introduced here: one is Duomiao coated fertilizer, with nitrogen:phosphorus:potassium:magnesium at 15:15:15:3, which is fairly good. The dosage can refer to the fertilizer instructions; just mix it evenly with the growing medium when potting. The other is Haokangduo, with a nutrient content of nitrogen:phosphorus:potassium at 14:12:14, which is also fine. For topdressing, commercial complete orchid fertilizers can be used, such as Lanjunwang, applied according to the instructions, or at a slightly lower concentration than the instructions; mainly by watering, and also by foliar spraying. There are many fertilizers of this type, with little difference among them; just choose one with a relatively good effect. Those with skills can also use commercial agricultural compound fertilizers (sulfur-based type is preferable, that is, produced with ammonium sulfate and potassium sulfate as raw materials), and so on. These fertilizers have a quick effect and good results, but their usage is not easy to master: generally water first, then according to the size of the pot, bury a few granules along the edge of the pot. Foliar spraying, as a supplementary form of topdressing, is mainly based on urea, because plant leaves absorb urea especially quickly. The concentration is generally one thousandth. During the flowering period, in winter and for sickorchid grass, 1/1000 potassium dihydrogen phosphate can also be sprayed, which can play a role in strengthening seedlings, promoting flowering, resisting pests and diseases, and resisting cold. Topdressing is generally done in the peak growing season of orchids; March to June and September to December are the main periods for topdressing. Topdressing should be based on the condition of the seedlings: when there are many seedlings, more should be applied; for thin seedlings, the concentration should be a bit lower. If you want more grass to grow and do not plan to let itflower, you can let the proportion of nitrogen be a bit higher; for grass that you want to flower and that has flower buds, there should be less nitrogen and more phosphorus and potassium. Before winter sets in, phosphorus and potassium should also predominate, which can enhanceorchid grass's resistance and help it sprout early the next year. When buying commercial fertilizers, pay attention to the labeling, and see whether there is a production license number, a registration certificate number from the Ministry of Agriculture and at the provincial level, and then also look at the nutrient content and the labeling of ingredients. These are stipulated by our country's laws and the national fertilizer label and marking standards. Those without these belong to illegal products, so everyone should pay attention when buying. (Liu Jingqiu)