What are the precautions for fertilizing orchids?
Do not fertilize until new roots have fully grown. After being moved around repeatedly, the orchid seedling's system is in a conservative, suppressed state. Its resistance is very weak, the wounds from broken roots have not yet healed, and it is highly susceptible to disease. When potting, besides making sure to use weakly acidic humus soil or ordinary plain soil, never apply a base fertilizer. Due to environmental changes, after potting the orchid seedling slowly recovers its functions in the moist substrate...
Do not fertilize if the orchid plant is not robust. During the fertilization period, if the orchid plant develops abnormally, new buds fail to emerge, the orchid leaves are grayish green, dull and lusterless, drooping with scorched tips, this indicates that the old roots are continuing to rot and new roots have not grown out. At this time, by no means should fertilizer be applied; only regular foliar spraying can be used to supplement nutrients. If it still cannot return to normal, the seedling must be lifted out, disinfected, and repotted with fresh soil.
Do not fertilize until new buds have grown larger. When the potted orchid seedling sends out leaf buds, it indicates that the orchid mycorrhiza has initially formed and new roots are gradually growing out and beginning to absorb nutrients, but at this time the new roots are still very short and few, with very weak function. To avoid affecting their development, no fertilizer of any kind should be applied. Only after the new buds have grown to 15 cm tall may a little fertilizer be applied. Do not fertilize if the flower buds are not plump. By early autumn, the new roots become increasingly strong and the flower buds begin to emerge. If the emerging flower buds are not plump or even deformed, it indicates that root function is still not vigorous and can only barely satisfy reproductive growth, not vegetative growth. Such orchids, lacking in reserve strength, also must not be fertilized; nutrients must still be supplemented through foliar spraying.
The five times not to fertilize, based on the seasons
Do not fertilize in early spring: although the spring temperature is very low, the orchid seedlings are just gradually reviving from dormancy and their activity is very weak. If fertilizer is applied at this time, it will not be fully absorbed by the orchid and will remain at the roots, causing fertilizer damage.
Do not fertilize in summer: when the temperature generally reaches around 35°C, the orchid seedlings enter a semi-dormant state, vegetative growth slows, and root activity weakens. Fertilizing at this time is likewise difficult for the orchid roots to absorb and easily causes fertilizer damage.
Do not fertilize in winter: the winter temperature is very low, the orchid enters its dormant period, the flower buds enter the vernalization period, vegetative growth stops, and no fertilizer can be applied.
Do not fertilize in bad weather: do not fertilize when it is raining or about to rain. First, the applied fertilizer is easily washed away by rain and lost; second, due to the weather change, the activity of the orchid roots is relatively weakened.
Do not fertilize at noon: it is best to fertilize in the morning or evening on a sunny day. At noon the temperature is relatively high, and fertilizing easily harms the orchid seedlings.
What fertilizer to apply
Decomposed farmyard manure: farmyard manure is a very good organic fertilizer, but it must be piled up and decomposed for more than one year before use. This fertilizer liquid can be diluted with water 10-20 times and poured on; apply it as close to the edge of the pot as possible, without touching the roots or the orchid leaves.
Chemical fertilizers: when applying chemical fertilizers, pay attention to the balance of nitrogen, phosphorus and potassium, and strictly control the concentration. For variegated-leaf seedlings, the synthesis of chlorophyll must be controlled, so nitrogen fertilizer should not be applied, nor should fertilizers containing manganese and magnesium (such as calcium magnesium phosphate fertilizer, etc.), because manganese and magnesium elements can accelerate chlorophyll synthesis. For flowering orchids, if cultivating large-petaled flowers, an appropriate additional amount of nitrogen fertilizer may be applied.
How to fertilize
Apply frequently and lightly, eat small meals more often: orchids do not need much fertilizer during their growth and development period. For vigorous, robust orchid plants, a dilute liquid fertilizer may be applied once every 10-15 days.
Foliar spraying is the main method: foliar spraying can both supplement the orchid plant's nutrition through absorption by the orchid leaves and avoid fertilizer damage from fertilizer touching the roots, making it the best fertilizing method for orchids. As long as during the growth and development period you persist in foliar spraying about once every 10 days, you can certainly grow orchids well without needing to fertilize into the pot. You can use 1:1000 monopotassium phosphate and 1:1000 boron fertilizer, or aloe liquid. This is because aloe contains a large amount of nutrients such as polysaccharides and amino acids, and contains more than 20 kinds of minerals, which can meet the nutrients orchids need, and aloe contains aloin, which can kill almost all germs and viruses, so after application there is no need to apply pesticides for disease prevention.
Rely mainly on natural organic matter. Natural organic fertilizers have relatively comprehensive nutrient elements, so no other fertilizers need be applied, and they are mild in nature with no side effects on plants. Chemical fertilizers, by contrast, easily make the substrate harden, and most chemical fertilizers are acidic; long-term application will make the substrate overly acidic and cause disease.