Why Are the Leaves of Your Phalaenopsis Orchid Splitting?
Many orchid growers encounter the situation where the leaves of their Phalaenopsis orchid split open, mostly splitting down the middle, and this is especially common in northern regions. First of all, split leaves will not cause fatal harm to the Phalaenopsis orchid. The reason the leaves split is mainly due to dry air, so try to increase the humidity as much as possible.
Newly purchased Phalaenopsis orchids are relatively more likely to have split leaves, because such orchids are generally grown in a greenhouse environment. High humidity plus rapid growth make the leaves both brittle and tender, and with one careless moment, when a leaf folds inward, it splits open with a crack right away. But growers need not worry; as long as it is kept dry, it will scab over and heal on its own.

Why Is a Newly Purchased Phalaenopsis Orchid in Poor Condition?
When we buy a Phalaenopsis orchid and grow it at home, the last environment the orchid left was a greenhouse, an environment with uniform temperature and consistently high humidity, and most importantly, an environment kept for long periods under the light conditions most suitable for Phalaenopsis orchids. Once it returns home, the humidity drops and the light fluctuates between high and low. This means that a newly arrived plant inevitably needs a period of adaptation and adjustment (its physiology will change in response to the new environment). This adaptation period is bound to come with some phenomena:
1> The leaves become soft and droopy; 2> The leaves stop growing; 3> New leaves are not as large as the original leaves; 4> The roots show signs of shriveling.
During this period, you need to use correct watering and lighting to gradually help it recover in the shortest possible time. Before it has recovered, it is recommended not to rush to fertilize. Also, let me share one experience: I never create humidity by misting, because when misting, the humidity is high for a few hours, and once the water dries, the humidity drops rapidly. The orchid may not know which humidity level it should adapt to. Moreover, water standing on the leaf surface for long periods is a taboo. Soft rot, blight, and Pellicularia fungi also like this kind of environment.