How to Distinguish Natural Leaf Shedding from Diseased Leaves in Orchid Cultivation

OrchidsCultivation：OrchidsThe Difference Between Natural Leaf Shedding and Diseased Leaves

Every year during the two seasons of spring and autumn, orchid growers may find that the orchid leaves in the pot suddenly turn yellow and shed, causing alarm. In fact, many of these are natural leaf shedding.

The necrosis is very slow, and sometimes the condition eases, leaving half a leaf behind (natural leaf shedding cannot leave half a leaf). Whereas withsoft rotdisease, the leaf first loses its luster (at this point the pseudobulb base has already rotted and died), and then dies from dehydration, at which point it can be gently pulled up, but it does not break off at the petiole. If orchid growers find natural yellowing leaves during these two seasons, it is most likely sending up new shoots, so there is no need to panic.

Every year, the two seasons of spring and autumn are precisely the season for sending up leaf shoots. Sending up new shoots requires a great deal of nutrients, and some old leaves will sacrifice themselves, transporting their stored nutrients to the place where new shoots are growing. The characteristics of leaf shedding caused by this metabolism are: the leaves turn yellow very quickly, generally taking only a few days from discovery to turning completely yellow; there is no obvious boundary between yellow and green; when the leaves turn yellow there are no symptoms of dehydration, and only after a few days does the whole leaf turn brown and dry up; after the leaves have turned completely yellow, at the browning stage a gentle touch will cause them to fall off naturally from the petiole; this kind of yellowing leaf generally occurs on old plants and old leaves, but not entirely. With root disease and leaf disease in general, the leaf necroses section by section, with obvious boundaries.