Advantages of foliar fertilization of Orchid and problems needing attention

Orchid (scientific name: Cymbidium ssp.): epiphytic or terrestrial herbs, with several to many leaves, usually on the base or lower nodes of pseudobulbs, distichous, banded or rarely oblanceolate to narrowly elliptic, base generally with broad sheaths and enclosing pseudobulbs, articulated. Racemes with several or many flowers, the colors are white, pure white, white-green, yellowish green, yellowish brown, yellow, red, cyan, purple. Orchids in traditional Chinese flowers only refer to several species of terrestrial orchids distributed in Chinese orchids, such as Chunlan, Huilan, Jianlan, Mulan and Hanlan, which are commonly referred to as "Chinese orchids". This kind of orchid is very different from the tropical orchid with large and colorful flowers, there is no eye-catching gorgeous state, no huge flowers and leaves, but it has a simple, quiet, elegant and elegant temperament, which is very in line with the aesthetic standards of the Oriental. It has been cultivated in China for more than a thousand years. It is reported that Gou Jian, the king of Yue, planted orchids in the mountains of Shaoxing, Zhejiang Province as early as the end of the Spring and Autumn period. After the Wei and Jin dynasties, orchids have been used to decorate the courtyard. In ancient times, people began to collect wild orchids, while artificial cultivation of orchids began at the palace. After the Wei and Jin dynasties, orchids expanded from court cultivation to private gardens of scholar-officials, and were used to decorate the garden and beautify the environment, as described in Cao Zhi's poem Qiulan was Changpo. It was not until the Tang Dynasty that the cultivation of Lanhui developed to general gardens and flower growers. For example, Li Bai, a great poet in the Tang Dynasty, wrote poems such as "the fragrance of orchids is far away, and the roots of Cymbidium grass flow".

Advantages of foliar fertilization in Orchid

1. Supply nutrients directly to prevent basin soil from hardening. 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, it can prevent the basin soil from hardening and improve the fertilizer efficiency.

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 take effect.

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

4. Make up for 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 measure to supplement nutrients is foliar fertilization. Foliar fertilization can be carried out all the year round, and foliar fertilization can be carried out in cooler weather in summer and mild in winter, which can make up for the deficiency of root fertilizer.

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

Problems needing attention in foliar fertilization of Orchid

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 solution concentration, which can improve the osmotic efficiency, and the effect is better, but we must pay attention to the appropriate.

3. The time of wetting orchid leaves. Generally requires the fertilizer solution to wet the orchid leaves in 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. The effect of rain soon after spraying is not good, so you should choose sunny evening or dewy early morning for foliar spraying, and 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 special attention should be paid to the back of spraying leaves when fertilizing. The same is true of other varieties of national orchids, 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 turbid water containing impurities should not be used. If tap water is used, it must be stored for more than one day until the chlorine is released.

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.