Matters needing attention for fertilization of orchids in winter

Orchids are generally not fertilized in winter, but in view of the limitations of orchid pot cultivation, and targeted fertilization can be used to achieve a certain purpose.

1. For the orchid plants that have not changed the soil for many years, the compound fertilizer with more balanced elements of N, P and K can be slightly applied, and the lower concentration is better.

2. In order to increase the cold resistance of orchids, 1500 times potassium dioxin phosphate can be sprayed on the leaves, once every 20 days, choose a windless sunny day, and keep the air smooth after spraying.

3. Low concentration nitrogen fertilizer can be applied to orchid plant and weak orchid plant without flower bud.

4. It is not suitable to apply fertilizer to the orchid plants which have been infected with bacteria and the root system is seriously damaged.

With regard to disease prevention and control, we should give priority to prevention, comprehensive treatment, early treatment, small treatment, and treatment.

1. Keep the environment clean, remove pathogens, adjust air humidity timely, and ensure good ventilation conditions. This is an effective measure to prevent bluegrass from pathogen infection.

2. Regular spraying of pesticides to prevent, people can spray carbendazim, methyl sulfur, medical chloramphenicol 1000 times before winter, ten days or half a month later. Preventive medication is recommended not to use Bordeaux solution to avoid blockage of leaf stomata and copper poisoning.

3. Check the leaves regularly to correctly distinguish between pathogenic diseases and physiological diseases. For pathogenic diseases, the lesion tissue should be removed as far as possible; for many parts of the leaves, the leaves should be removed and burned, and then sprayed with medicine. for Yilan with high ornamental value, it can be treated by acupuncture heat conduction method, and then drug spray (see notes on acupuncture heat conduction method).

About heat preservation and anti-freezing. Due to the single soil structure of potted orchids, she does not have the heat released by the deep soil heat of wild orchids and the rich humus layer of topsoil, the heat released by microorganisms, let alone the microclimate formed by the mountain jungle, and freezing damage will occur when the temperature is below zero. It can be covered with straw, build a simple greenhouse, move people indoors, and receive full light at the same time. The temperature should be controlled above zero and about ten degrees, which not only ensures that the orchid plant has a good vernalization period but also does not break its normal dormancy.

The winter cultivation and management of orchids is a subject with great connotation, so it is not appropriate to talk about how to water, fertilize and prevent diseases in winter. Because the factors that affect the normal physiological activities of orchids are complex, they are not only related to each other but also restrict each other. For example, the permeability of the plant determines the amount of watering, and the amount of watering affects the growth of the root system. How can we keep these factors in a dynamic balance? This requires that when we cultivate orchid grass, we should comprehensively consider all aspects of factors, especially according to their own specific conditions of flower cultivation (such as local climate, pot soil plants, environment, etc.) to take corresponding measures. I wish everyone can raise bluegrass well.

Note: acupuncture heat conduction therapy. This method is the inspiration of Xu Dongsheng, an expert in orchid, who burned the disease spot with cigarettes and summed up through practice. It has the advantages of killing (burning to death) bacteria quickly, safe and harmless, small wound and so on. It is especially suitable for foliage plants.

Acupuncture heat conduction method is divided into two methods: cold needle heating acupuncture and hot acupuncture. The so-called cold needle heating acupuncture, that is, first take a metal needle (according to the size of the disease spot, leaf thickness, select needle thickness and needle material) with alcohol disinfection, the needle perpendicular to the center of the disease spot. Burn the other end of the needle with a burning flame (such as a lighter, candle) so that heat is transmitted along the needle around the lesion, burning the pathogen to death. The hot needle needling method is to heat the sterilized needle to a certain temperature with a flame, and then quickly perpendicular to the center of the leaf prickling spot. The former is suitable for the infection of larger lesions, while the latter is suitable for smaller lesions.

In addition, whether it is cold needle method or hot needle method, the thermal conductivity of needles of different materials is different, and the speed of heat conduction of needles of different thickness is also different. Interested orchid friends can first do an experiment on the same thickness of orchid leaves to determine the size of the flame and heating time, and then start the real treatment, the treatment area of burns is slightly larger than the disease spot. (Bao Dongping)