The leaves of Jian Lan turn yellow.

Jianlan watering can not be too frequent, and do not set a rigid interval, should be in the basin soil dry to about 80% before watering, generally can be in the topsoil dry, and then use a tool (such as bamboo sticks, etc.) to turn about 5 cm of basin soil, if you see dry, watering, if still wet, there is no need to water. Note that if the outdoor maintenance of the orchid can not be carried out in accordance with the above method, the topsoil should be watered as soon as it is dry, and it should not be kept moist or waterlogged. There is stagnant water in the basin bottom tray and should be poured out in time. In addition to proper shading in summer, the conservation environment should be given better light at other times, so it is not suitable to be placed in the shade for a long time.

Now, check the base of the lower stem, such as the subcutaneous tissue is green, the skin is firm and has no signs of loosening, indicating that there is no rot and drying, and it can be gradually recovered through the above-mentioned normal light environment, reducing watering and other measures. If the subcutaneous tissue of the stem is brown or dark brown, and there is a liquid outflow, and the skin is loose and inelastic, it means that the stem of the whole plant has rotted and there is no significance for further maintenance. At this time, if the top branches are still green, the cuttings can be cut off in time in the clean river sand to cultivate new plants, to maintain a high air humidity, the river sand does not need to be watered too frequently.

(2) methods: yellow leaves appear, depending on their occurrence characteristics, there are the following situations:

First, the water is yellow. Due to excessive watering, it is characterized by no obvious change in the old leaves and yellowing of the young leaves, which should be controlled immediately.

The second is drought and yellow. Due to the lack of water and drought, it is characterized by the yellow of the old leaves from the bottom to the top. If the lack of water is a little longer, the yellow leaves of the whole plant, or even death, should be watered in time.

The third is fat yellow. It is caused by excessive fertilization or high concentration, characterized by thick, shiny and uneven young leaves, and fertilizer, ploughing and watering should be controlled.

Fourth, hungry yellow. It is caused by insufficient fertilizer, low fertilization concentration and long interval of fertilization; it is characterized by yellow young leaves and tender stems, which will cause yellow leaves and even death of the whole plant if it is not fertilized in time; for flowers lacking fertilizer, do not apply a large amount of thick fertilizer at one time, so as not to cause root burning.

Fifth, iron deficiency yellow leaves. Due to the great change of soil fertility conditions, the phenomenon of yellow leaves often appears in the greenhouse, which is characterized by obvious young leaves, light old leaves, yellow mesophyll, green veins and a typical network, which can be solved by using ferrous sulfate solution. the method is as follows: 7 parts of cake fertilizer, 5 parts of ferrous sulfate and 200 parts of water.