Phosphate Fertilizer and Potassium Fertilizer
Plant Management Tips: Experiences about common flower care knowledge, phosphate fertilizer and potassium fertilizer. The following article provides detailed answers by the editor.
Many flower enthusiasts are aware of the functions of phosphate and potassium fertilizers, but there may be some blind spots in their use in home gardening. This article presents insights from flower enthusiasts on the application of phosphate and potassium fertilizers in flowers, which is worth reading.
Almost all flower enthusiasts know about the relationship between phosphate fertilizer and flowering. Phosphate fertilizer can promote flowering, making the flowers larger and more fragrant. Therefore, many people spray phosphorus and potassium fertilizers excessively during the flowering season, using a certain brand's fertilizer with an extreme NPK ratio of 1:3:1. However, is this really the case? Is phosphate fertilizer a magic remedy for flowering plants? Is high-dose phosphate fertilizer a flowering elixir? Phosphate fertilizer is indeed important for flowering plants, but even if it is important, it should still maintain a general ratio with nitrogen and potassium. We always talk about the three elements of fertilizers: nitrogen, phosphorus, and potassium, and place phosphate fertilizer before potassium fertilizer. However, according to multiple analyses, most crops (including flowers, and even flowers during the flowering period) absorb more potassium fertilizer than phosphate fertilizer, and many crops absorb significantly more potassium fertilizer than phosphate fertilizer, sometimes several times more.
The dry matter composition of plants, although different plants have different proportions of the three major elements, nitrogen generally has the highest proportion, followed by potassium, and phosphorus is the least, which directly proves the plant's absorption ratio of the major elements.
For the flower variety that the flower enthusiasts pay the most attention to, the Chinese rose, flower farmers in Yunnan have a recommended ratio for fertilizer blending. The ratio during the growing period is 3:1:2 (nitrogen:phosphorus:potassium), and during the flowering period, it is 3:1:3. Is this surprising—why is there so little phosphate fertilizer? Is there too much nitrogen fertilizer? Is there too much potassium fertilizer? In fact, it should not be surprising; this is the fertilizer ratio principle followed by professional-level flower growers.
The importance of potassium is further demonstrated by tissue culture, which involves using a culture medium to grow a very small piece of plant tissue. The medium contains all the nutrients needed for the growth and propagation of this small piece of tissue. The most classic medium is the MS medium, which has a formula ratio of three major elements: potassium nitrate:ammonium nitrate:potassium dihydrogen phosphate as 1900:1650:170. Surprised again? Yes, potassium dihydrogen phosphate is only 170, not 1700. Of course, tissue culture is only for growing seedlings and cannot be used to grow plants to flowering, so it is not representative. However, it undoubtedly proves the importance of potassium, as plants usually require more potassium than phosphorus during growth.
The ratio of fertilizers and the promotion and antagonism between elements.
Various plants have different fertilizer element requirements. Some plants may have special needs and dependencies on certain elements, such as the common wire grass, which has a special dependency on calcium. If you see wild wire grass in the wild, you can be sure that the soil in that area is rich in calcium. Of course, the special needs of plants for certain elements need to be concluded through long-term cultivation observations or fertilizer tests. For ordinary cultivated plants, we cannot accurately apply fertilizers in daily cultivation management. Imbalance in the ratio of elements, excess or deficiency, can affect plant growth. The most common excessive nitrogen causes plant overgrowth, delays flowering and fruiting, so many flower enthusiasts avoid nitrogen fertilizers and prefer to use a lot of phosphate fertilizers, not knowing that excessive phosphate fertilizers can also cause adverse effects, such as premature entry into the reproductive stage with slow plant development, leading to weak plant growth, increased respiration, and inability to accumulate nutrients, resulting in smaller or even deformed flowers. There are complex relationships between fertilizer elements in terms of absorption and utilization, including promotion and antagonism. Promotion means that one element can promote the absorption of another, while antagonism means that one element can prevent another from being normally absorbed. Deficiency symptoms caused by the lack of certain elements are called deficiency diseases. Some deficiency diseases are indeed caused by a lack of soil elements, but some are not due to element deficiency, but rather to the inability of another element to be absorbed normally due to an excess of a certain element. For example, a common mistake made by many flower enthusiasts is the excessive use of phosphate fertilizers, which can cause iron deficiency symptoms with yellowing leaves, and applying iron preparations at this time is not very effective. This is because phosphate fertilizers inhibit the absorption of iron, and reducing phosphate fertilizers will be effective. Common promotion and antagonism between fertilizers are not complete and can be used as a reference:
Phosphorus and magnesium help in absorption; excessive phosphorus can hinder potassium absorption, cause zinc fixation, leading to zinc deficiency, and hinder copper and iron absorption. Potassium promotes boron absorption and aids iron absorption. Excessive potassium hinders nitrogen absorption and suppresses calcium and magnesium absorption, which can cause脐腐 and leaf yellowing. Manganese has a mutual absorption effect with nitrogen, potassium, and copper; excessive manganese suppresses iron absorption and can trigger magnesium deficiency. Moderate copper (G-Y) can promote manganese and zinc absorption. Excessive zinc suppresses manganese absorption and reduces the availability of phosphorus. Excess of potassium, calcium, nitrogen, or phosphorus can affect zinc absorption. Magnesium and phosphorus have a strong mutual dependence on absorption, which can make the plant grow vigorously, increase female flowers, and aid in silicon absorption, enhancing the plant's disease resistance and stress tolerance. Magnesium and potassium have a significant mutual inhibition effect; excessive magnesium results in thin stems and small fruits, making it prone to fungal diseases. Calcium and magnesium have a mutual absorption effect, which can make fruits mature early, with good hardness and storability.
Therefore, when applying any fertilizer, it is important to maintain a balance. Potassium dihydrogen phosphate is a good fertilizer, but it should not be used randomly. For home gardening, especially potted plants, it is best not to use a single fertilizer but a compound fertilizer. If only a single element fertilizer must be used, be sure to pay attention to the amount to avoid an excess of a single fertilizer.
The shared experiences about phosphate and potassium fertilizers for green plants and flowers are hoped to be of help in your life!