Orchid foliar fertilization points and precautions, edible fungi pest control

In the cultivation of national orchid, the absorption of nutrients by orchids mainly depends on their own roots, and there is little need for extra-root fertilization. therefore, extra-root nutrition is not as important as root nutrition, but under special circumstances, extra-root nutrition still has a certain significance, for example, when the orchid emerges, it is necessary to apply fertilizer in time to make up for it. In practice, foliar fertilization is relatively easy to eliminate the symptoms of element deficiency in orchids. In addition, foliar fertilization is also a better way to make up for fertilizer for rotten root orchid plants.

I. the advantages of foliar fertilization of orchids

1. Supply nutrients directly to avoid the consolidation of basin soil. Some nutrient elements, such as iron (Fe), manganese (Mn), zinc (Zn), etc., are easy to be fixed after being applied to basin soil, and their effectiveness is greatly reduced. If it is changed to foliar fertilization, the consolidation of basin soil can be avoided and the fertilizer efficiency can be improved.

2. Nutrients run fast and can be effective in a short time. Foliar fertilizer spraying is more effective than root fertilization, and it can ensure the timely supply of nutrients. Practice has proved that foliar spraying urea can be effective in 1 to 2 days, while it takes 5 to 6 days to apply urea into basin soil. For example, phosphate fertilizer, foliar spraying once can take effect, but root fertilization takes 10 days to achieve effect.

3. Save fertilizer without harming the roots. The amount of foliar spraying fertilizer is usually only about 20% of the amount of fertilizer applied in basin soil. Take spraying "Huabao" as an example, 1 gram of Huabao is dissolved in 1 liter of water (that is, adding 1000 times of clean water), spraying orchid leaves on both sides, the dosage is small, only 1 inch 5 of the amount of plant material in the watering basin is enough. Foliar spraying of trace element fertilizer not only saves the amount of fertilizer, but also avoids the damage to the root of orchid plant caused by uneven application of basin soil.

4. To fill the deficiency of stopping the application of root fertilizer. In the hot summer and cold winter every year, root fertilization must stop, but it does not mean that orchid plants do not need nutrients. At this time, the safest way to make up for nutrients is foliar fertilization. Foliar fertilization can be carried out all the year round, and foliar fertilization can be carried out when it is cooler in summer and softer in winter, which can make up for the deficiency of stopping root fertilizer application.

5. Save time and reduce the times of spraying. Foliar fertilization can be carried out together with insecticidal sterilization and other processes. In spraying foliar fertilizer solution, adding appropriate amount of omethoate (killing shell insects, etc.) and 75% chlorothalonil (sterilization), not only applied fertilizer, but also killed insects and sterilized, which not only saved time, but also reduced the number of spraying, you can get twice the result with half the effort.

2. Problems that should be paid attention to in foliar fertilization of orchids.

1. Insoluble fertilizers can not be used. The rate of foliar absorption of different fertilizers with the same nutrient elements is different. With the same potassium fertilizer, the fastest foliar absorption rate is potassium chloride, followed by potassium nitrate, followed by potassium dihydrogen phosphate; the same nitrogen fertilizer, the fastest foliar absorption rate is urea, followed by nitrate nitrogen fertilizer, followed by ammonium nitrogen fertilizer. The fertilizer used for foliar spraying can only be water-soluble, and the insoluble fertilizer can not be used.

2. Pay attention to the solution concentration and reaction. The principle is that under the premise that the leaf surface is not damaged by fertilizer, properly increase the concentration of the solution, which can improve the infiltration efficiency, the effect is better, but must pay attention to the appropriate.

3. The time of wetting orchid leaves. Usually ask the fertilizer solution to wet the orchid leaves for 30 minutes to 1 hour, so that the absorption is fast and the effect is good. If it is killed soon, the effect will be very poor. Soon after spraying, the effect of rain is not good, so we should choose sunny dusk or early morning with dew for foliar spraying, the windless weather is better.

4. The spraying position should be reasonable. Stomata are the entry and exit of gas and water in and out of plants during photosynthesis and respiration, so foliar spraying should be reasonable. For example, the stomata of Cymbidium leaves account for about 85% on the back and only 15% on the front, so pay special attention to the back of spraying leaves when fertilizing. The same is true of other varieties of national orchid, with emphasis on spraying the back of the leaves.

5. the water quality should be clean. The water quality used to dilute fertilizers should be clean and muddy water containing impurities should not be used. If tap water is used, it must be kept for more than one day until chlorine is distributed.

6. Do not apply single fertilizer for a long time. Orchids should be sprayed with different fertilizers in different growth periods, and only single fertilizers should not be used for a long time. For example, when new buds of orchids are unearthed in spring, they should be mainly nitrogen fertilizer, such as urea, Huabao (No. 5), etc.; from the beginning of July to the end of August, in order to promote the formation of flower buds, mainly phosphate fertilizer, such as Huabao (3), potassium dihydrogen phosphate and so on.