The root cause of orchid leaf disease

1) the leaves of orchids are yellowed and grow normally: the light is too strong. 2) the leaves of orchids turn yellow and the new buds are smaller: excessive light, lack of nitrogen fertilizer and necessary humidity. 3) yellowing and shedding of old leaves of orchids: caused by normal aging or turning over pots. 4) rapid yellowing and shedding of old leaves of orchids: too much watering, too often and improper planting. 5) the new leaf tip of orchid is scorched: excessive fertilization and unclean planting materials. 6) the focal tips of new leaves and old plants of orchids are black: excessive dampness and heat in the basin, and rotten roots in the roots. 7) after the new bud of orchid is unearthed, it stops growing again: there are rotten roots or unclean things next to the new bud, open the breeding material around the new bud, remove the unclean matter and resume growth. 8) there are scorched spots on the leaves of orchids, and there are no yellow on the periphery: scorching spots in the hot sun. 9) the shrinking head appears at the end of the orchid leaf: the water temperature of watering is too high; the temperature is too high when watering; showers are caught in high temperature in summer and so on. 10) Orchid new bud rotten heart: after watering into the bud core, the water can not be evaporated and absorbed, and the unclean reproductive wood in the basin leads to leaf rot, etc. 11) there are water immersion on the periphery of orchid leaves: excessive humidity, basin humidity and air humidity produce asphyxiation, accompanied by leaf rot bacteria. Poor ventilation and ventilation. 12) there are chloasma on the leaves of orchids: caused by heat at the roots. 13) there are irregular maculae and necrotic mesophyll tissue on the leaves of orchids: virus disease is also caused by "Balas". 14) there are small yellow spots on the leaves of orchids: caused by beetles. 15) the orchid leaves appear purple-black, and the back of the leaves is still green: caused by low temperature frost. Lack of phosphate fertilizer can also occur. 16) dehydration of orchid leaves and shrinkage of pseudobulbs: caused by long-term over-drying and dehydration in the basin.