First, how yellow is the water?
The young leaves at the top of the flower turn yellow, the old leaves turn yellow and the new buds shrink. This is because watering too much, raining or watering too much, resulting in too wet flowerpots, lack of oxygen in the soil and rotting fibrous roots. The correct way is to loosen the soil frequently and control watering.
Second, water shortage is yellow.
The top leaves of potted flowers are normal in color, and the lower leaves gradually dry up and fall off. This is generally because the pot soil is too full and watered for a long time, which leads to the aging of the lower leaves and branches. Excess basin soil should be properly removed and properly watered to keep the soil moist.
Third, the lack of fat yellow.
The leaves of flowers are thin, tender and yellow, which are generally caused by large flowers and small pots or pots that have not been changed for a long time and insufficient fertilizer. Fertilizer and water should be gradually increased, but be careful not to be too thick. Potted flowers are changed once every one or two years. Tree bonsai is changed every 2~4 years. When changing pots, add a small amount of base fertilizer to the bottom of pots and change some new soil.
Fourth, fat is harmful to yellow.
The leaves are uneven, the new leaves are thick, and the old leaves turn yellow, mostly caused by fat. Water Qin Ying, suspend fertilization, sow some rapeseed or other seeds in the basin, and pull them out after emergence to consume the fertility in the basin.
Verb (abbreviation of verb) metabase yellow
Camellia, azaleas, orchids, white orchids, gardenias and other flowers like acidic soil, because the soil is alkaline, so the leaves will gradually turn yellow, so you can water them with water soaked grass or coated with ferrous sulfate, and soon the leaves will turn green.
Six, pests and diseases yellow
Yellow spots appeared on the leaves, which were destroyed by scale insects; The leaves are rough, dry and yellow. Because of the harm of red spider, 70% trichlorfon 1000 times solution or 40% dimethoate 2000 times water can be sprayed. The yellowing of leaves caused by virus will spread rapidly, so it should be removed and burned in time, and then sprayed with carbendazim or Bordeaux mixture to prevent it. Don't spray too much, or there will be drug damage.
Seven, lack of light and yellow
Flower pots are easy to turn yellow when placed indoors in places where the sun has not been seen for a long time. Jasmine, white orchid, etc. Like sunlight, leaves turn yellow if there is not enough light. On the contrary, some evergreen, upside-down golden bell, pearl orchid and so on. Like cool, in case of high temperature and improper shading, the leaves will turn yellow.