Basal stem rot and root rot are two of the most common diseases that affect the Christmas cactus. If you notice abnormal spots or areas of browning on your plant, trim them away as soon as possible. This will stop any existing disease from spreading further.
Prevent rot by only watering your Christmas cactus when the soil looks dry or when it feels dry to the touch. Keep a close eye on the leaves so you can quickly identify potential signs of disease before they spread.
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