What are the fertilization methods? A side-by-side look at the pros and cons

At present, most general growers dissolve a set amount of solid or liquid fertilizer in several times its volume of clean water to make liquid feed. But each person follows their own method, believing it to be ideal. Among these, roughly three are most widely adopted. For convenience of explanation, we may call them here: the concentrated-fertilizer flush method; the micro-fertilizer continuous method; and the dilute-fertilizer leave-it-alone method. The so-called "concentrated fertilizer" here means the highest concentration of the usual set dose. "Dilute fertilizer" means one reduced by about 60% to 80% of the usual set dose. "Micro-fertilizer" means liquid feed reduced to 10% to 20%. The advantages and disadvantages, gains and losses, of the above three fertilization methods are described separately below: A. Concentrated-fertilizer flush method: 1. Method: Use liquid feed at the usual set dose, the highest concentration. After applying it, wait one to two hours, with no fixed time, then pour on a large amount of water, flushing the orchid plants and pots. This makes the fertilizer contained in the pot flow out entirely with the water. 2. Reasoning: Those who use this method say: unless the amount of fertilizer reaches a considerable concentration, no fertilizing effect can be obtained. Also, plants absorb fertilizer as animals take in food, and a brief time is enough. After applying the fertilizer, let it be absorbed for a set time; when the time is up, wash it off with water, and the best fertilizing effect can still be obtained. It also prevents fertilizer from lingering in the pot and causing the medium to acidify and bacteria to multiply. 3. My humble opinion: (the author's opinion) The vital functions and physiological states of plants and animals are inherently different. To speak of orchid plants absorbing fertilizer in the same breath as animals taking in food is not necessarily entirely appropriate. This method is generally regarded as follows: if concentrated fertilizer is required, why flush it away? Rather than flushing at every turn, it would be better to apply a somewhat weaker fertilizer! Moreover, from applying the fertilizer to flushing it away, the length of this period differs according to each person. If the timing of the flush is wrong, or the flushing technique is improper, there is a risk of fertilizer burn! Everyone should remember this! Fertilizer burn in plants is the phenomenon in which a plant takes in overly concentrated fertilizer, causing a stimulus it cannot bear, so that its vital functions are damaged. If the liquid feed received by an orchid plant is too concentrated, it immediately suffers an unbearable stimulus, and although the time is short, it is enough to cause fertilizer burn! Therefore the concentrated-fertilizer flush method seems applicable only to experienced experts; beginnersgrowing orchidsneed not, it seems, take this risk! B. Micro-fertilizer continuous method: 1. Method: Dissolve 10% to 20% of the usual set dose into liquid feed, using fertilizer as water and water as fertilizer, and with each routine watering, continuously apply a very mild fertilizer. 2. Reasoning: The rationale held by those who use this method is that fertilizer's stimulation of orchid plants often causes fertilizer burn, and as a surefire way to prevent fertilizer burn, an extremely mild liquid feed is used continuously, with fertilizer as water. This can absolutely avoid fertilizer burn and also increase the plant's opportunities to absorb fertilizer. More frequent applications make up for the mild dose. 3. My humble opinion: When fertilizing, one must adjust according to the health condition of the orchid variety. That is, when applying liquid feed of a set concentration, give the healthy and strong plants the usual amount. For plants of medium health or especially prized varieties, apply a little less. For weak plants and old plants, even less, or none at all. For those repotted less than half a month ago, absolutely do not apply. This is a principle that must not be violated when fertilizing! Fertilizing should also depend on the weather. That is, in hot weather when the temperature rises to about 33°C, or in cold weather when the temperature drops below 10°C, or on gloomy days of continuous plum rain, fertilizing is absolutely forbidden, and this is another taboo that should be observed when fertilizing! If micro-fertilizer is applied continuously, the mild dose will leave strong orchid plants short of nutrients. It will also be more than weak plants, which should be spared fertilizer, can bear, creating a state of both excess and deficiency, and violating the principles and taboos of fertilizing! C. Dilute-fertilizer leave-it-alone method: 1. Method: Dissolve 60% to 80% of the usual set dose into liquid feed; after applying, leave the fertilizer in the pot, letting the orchid plants absorb it freely, until the next watering, when it is washed away with the water applied. 2. Reasoning: A light, thin liquid feed carries absolutely no risk of fertilizer burn, and one can also adjust the amount up or down by applying more or less according to the health condition of the orchid plants. It has neither the drawback of excess nor of deficiency, and one can also observe the taboo of stopping fertilization during severe heat, severe cold, or plum rain. 3. My humble opinion: This method is relatively gentle and does not go to extremes. The author has used this method for more than ten years, continuing it to this day, and has seen only its benefits and none of its drawbacks. If it is said that this method lets fertilizer accumulate in the pot for a long time, easily causing the medium to acidify and bacteria to multiply. True! But after the dilute fertilizer is applied, by the next watering it is likewise washed away by the water; although the pot holds fertilizer for a somewhat longer time, there is really no great harm! Because although concentrated fertilizer stays in the pot for a short time, its concentration is high. Dilute fertilizer lingers in the pot a little longer, but its concentration is low. As for the concerns about the medium acidifying and bacteria multiplying, the pros and cons of the two are not much different. The only difference is that dilute fertilizer absolutely does not cause fertilizer burn! (Wu Anlu)