Why do orchid leaves turn yellow after repotting? Don't worry

A fellow orchid grower asks: One month after repotting, the orchid's leaves are turning yellow - is it sick? One month after potting, yellowing leaves generally point to two possibilities, and you can tell which by the order in which the leaves turn yellow.

First, the leaves turn yellow from the base upward, and when the leaf stalk is nearly yellow and withered the leaf tip is still green - this is disease. It is usually stem rot or soft rot, root rot and the like. It is very likely that the plant went into the pot carrying the pathogen, and it needs to be dealt with promptly, otherwise it may affect the whole pot. How to handle it: unpot the plant, cut away the diseased growth, and apply a mixed powder of carbendazim and mancozeb to the wound.

Second, the leaves turn yellow starting from the tip, beginning with the oldest growth and progressing downward in turn - this is normal leaf dieback. When an orchid is newly potted, its new roots have not yet adapted to the soil environment and cannot absorb and supply the nutrients the whole plant needs. Out of the biological instinct to keep reproducing, the plant seizes the energy reserves of the old growth to supply the new generation of growth. This phenomenon continues until the orchid has settled into the pot and the orchid roots can independently take on the role of nutrient transporters.

If there is a problem with the growing medium, or with the way it was planted, the orchid will never settle into the pot. Then this yellowing of the growth will gradually spread from the old growth to the next generation, until the whole pot dies.

Fellow orchid growers can use this as a reference. If you have any other questions, you are welcome to leave a comment in the comments section.