Causes of Yellowing Phalaenopsis Leaves and How to Handle Them

Phalaenopsis is an epiphytic orchid with very high ornamental value. Moreover, Phalaenopsis plants are able to grow by absorbing nutrients from the air. That is why there are quite a lot of people growing Phalaenopsis nowadays, and when we grow Phalaenopsis, the phenomenon of yellowing Phalaenopsis leaves often occurs. So what causes Phalaenopsis leaves to turn yellow? And how should they be handled? Let's take a look together with the editor below!

1. Sun-yellowing

Cause: Light is very important for the growth of Phalaenopsis, but if the light exposure time is too long or the light intensity is too strong, it can very easily cause Phalaenopsis leaves to turn yellow. This is because if the light is too strong, the Phalaenopsis leaves cannot withstand it, water evaporates too quickly, and in severe cases they may be scorched, resulting in the yellow leaf phenomenon. Sun-yellowing mainly shows as the light-facing side of the Phalaenopsis leaves and the upper leaves being yellow-green, while the shaded underside remains normal.

Handling method: If sun-yellowing occurs, then we must promptly control the light properly. Reduce the light exposure time for the Phalaenopsis and lower the light intensity. Do not let it receive light during midday and during strong-light periods such as summer. For leaves that have already been sun-yellowed, placing them in weak light in the morning and afternoon will allow them to gradually recover. However, if sunburn spots have formed, because the tissue at the sunburn spots has already necrotized, they cannot recover.

2. Drought-yellowing

Cause: Phalaenopsis rather likes to grow in a humid environment. Even when budding in winter, the air humidity should be kept at around 70%. During flowering, the air humidity should also not be lower than 50%. The soil should be kept alternating between dry and moist; if the Phalaenopsis aerial roots are too dry for too long, then the old leaves at the lower part of the plant will begin to turn yellow due to excessively low humidity and lack of water, and the leaves will also noticeably become thinner.

Handling method: Leaves that have yellowed due to drought do not have many other symptoms. At this time, promptly cut off the yellow leaves and promptly replenish water by watering, which can effectively alleviate the yellowing phenomenon. However, prevention should still be the main focus, watering appropriately and frequently spraying around the plant.

3. Root rot

Cause: Another main cause of yellow leaves in Phalaenopsis is root rot. Root rot is one of the most common; if the Phalaenopsis leaves turn yellow, droop, and are yellow-brown with rot, then it is generally caused by root rot. After root rot, the Phalaenopsis roots cannot absorb nutrients, and the leaves will also turn yellow due to malnutrition.

Handling method: For root rot, we must promptly remove the plant from the pot, cut off the rotten roots, disinfect them, and replant. And prevention should also be the main focus; Phalaenopsis root rot may be caused by overwatering, poor soil permeability, or excessive fertilizing. So everyone should pay close attention; after dealing with root rot, use fresh medium for replanting, cut off the flower spikes, and let it re-establish itself.

The above is a brief introduction to the causes of yellowing Phalaenopsis leaves and the handling methods. That is all for today's introduction; this article is for reference only, and we hope it can help everyone!