In the period of growing new leaves of Cycas, it is necessary to carry out full Yang curing until the leaves are hardened and then moved to the half shade. If sufficient light is not guaranteed in the growth period, the leaves will turn yellow.
Improper watering can be divided into over watering and under watering. In the growth period of new leaves, it is necessary to provide sufficient water, but do not let the basin soil wet for a long time, otherwise the root system is easy to lack of oxygen, resulting in poor plant growth, and then the leaves show yellowing. Of course, water shortage will also cause the leaves to turn yellow. The specific characteristics are that the leaves turn yellow from bottom to top, and the old leaves turn yellow first. If not watered in time, the leaves of the whole plant will turn yellow, or even die.
If the fertilization is too much, or the fertilization concentration is too high, the leaves of Cycas will also turn yellow. The young leaves are thick and glossy with uneven surface. The solution is to control the use of fertilizer, medium tillage and appropriate watering. If the young leaves and young stems of Cycas begin to turn yellow at first, it is probably caused by insufficient fertilization and too long interval of fertilization. At this time, fertilizer should be applied in time, otherwise the yellow leaves of the whole plant may even die. It should be noted that a large amount of concentrated fertilizer should not be applied at one time, otherwise it will cause root burning.
Cycas like slightly acidic sandy soil, and the alkalization of soil will also make the leaves of Cycas yellow. You can use ferrous sulfate solution to irrigate the basin soil 500 times, once a week, continuously irrigate several times, which can alleviate the yellowing degree of leaves.
Diseases and insect pests are also one of the causes of yellow leaves of cycads. Carefully observe whether there are red spiders and scale insects on the leaves, and spray them in time for corresponding control. If yellow spots appear on the leaves, you can spray Carbendazim and other fungicides.
