What if the leaves of Cymbidium turn yellow? what if the leaves of Cymbidium turn yellow?

In the process of growth, the leaves of Cymbidium often turn yellow. There are four main causes of yellow leaves, one is sunburn. Second, the water and fertilizer is too large. The third is excessive alkali or acid in the soil, and the fourth is the lack of nitrogen fertilizer.

The solution to the yellowing of Cymbidium leaves

1. Put the orchid indoors or under the shade where there is scattered light to avoid direct sunlight and keep the temperature at 15-25 ℃.

2. Change the culture soil, cut off the rotten roots, and control the use of water and fertilizer.

3. Change the pH of the culture soil to make it neutral or slightly acidic, and pH6.7~7 is suitable, so don't irrigate ferrous sulfate fertilizer and water.

4. increase the fertilizer and water of fermented cake. If we pay attention to cultivation, the phenomenon of yellow leaves will be eliminated.

With the growth of the plant, the root system will gradually increase, and the pot needs to be changed. When changing the basin, it is necessary to remove the old roots, rotten roots, and add new culture soil, so as to promote growth. Generally, the basin needs to be changed every 2 to 3 years, which can be carried out in spring and autumn. Do not water immediately after changing the basin, so as to avoid infection and decay of the root wound.

Attached: prevention and control of diseases and insect pests of Cymbidium

1. Rot: mainly occurs in leaf sheaths or roots. Prevention and treatment methods: can cut off the site of the disease, sunshine, ventilation, prevention and treatment of wound moisture.

2. Leaf spot disease: the initial symptoms are small brown spots, but in the later stage, the disease spots are dry and black particles appear in the center. Control method: ① can spray 5% carbendazim 1000 times solution. ② sprayed 70% topiramate 1500 times solution.

3. Soft rot: at the beginning, it looks like oil spot, light yellow, transparent, and then gradually turns brown, soft rot or dry. Prevention and treatment methods: ① can strengthen ventilation and soil disinfection. ② can spray leaves or smear disease spots with 5000 times diluted solution such as penicillin, streptomycin or oxytetracycline.

4. Scale insect: it is the main pest of Cymbidium, which mostly occurs in summer and mainly harms leaves. Prevention and treatment: it can be sprayed with 8-1000 times of imidophos.