Epiphyllums are hybrids of tropical epiphytic cacti species. Sometimes called orchid cactus, epiphyllum plants bloom flowers in various shades of pink, purple, yellow, orange, white and red. While epiphyllum are hardy plants, they are still susceptible to a few common diseases.
Epiphyllums are susceptible to various bacterial and fungal pathogens that cause black rot diseases. These plants are also vulnerable to fungal leaf spot, particularly during humid winters.
Black rot disease damages an epiphyllum's root system, which causes the plant to turn yellow. Fungal leaf spot symptoms include black or brown spots appearing on the leaves.
Potential pest problems include mealy bugs, slugs, aphids, mites and scale. Epiphyllum plants frequently turn a yellowish colour when they receive too much sunlight.
Infected plant tissue should be removed and destroyed before the disease spreads to the other epiphyllums. Insecticides typically rid plants of the pests.
Epiphyllum plants should be planted far enough apart to promote good air circulation. Adequate ventilation reduces the risk the pathogens spreading.
Epiphyllums generally thrive in partly sunny locations. These plants should be watered only when the soil is dry to the touch.