Why the outer old leaves of Cymbidium turn yellow and fall off

The main reason for the yellowing and shedding of the old leaves in the outer layer of the orchid: ① in the normal growth process, it is necessary to alternate the metabolism of the new and old leaves, with the new young leaves growing, the old leaves naturally wither and fall off, which is a normal physiological phenomenon.

② basin soil is caused by improper drying and wetting. Sometimes the basin soil is very dry, and sometimes there is a lot of watering, so that the water supply can not meet the needs of the weak growth of the old leaves, which leads to the withered and yellow shedding of the old leaves. Therefore, the basin soil should be kept moist, not sometimes too wet, otherwise it will not only produce the outer layer of old leaves withered and yellow, but also easy to produce rotten roots, affecting the normal growth and flowering of Magnolia.