Orchid cactus (Epiphyllum) are hanging plants with big, cup-shaped flowers. Most orchid cactus hail from Mexico, and new hybrids capitalize on the plant's beautiful flowers to create larger, showier flowers in a wide range of colors. Orchid cactus make good house plants because they like conditions similar to those found in the typical house. Bright, indirect light, and higher humidity around 50-60% will keep orchid cactus happy.