The orchid cactus (Epiphyllum spp.) is a botanical paradox. It isn't really an orchid, and it looks much more like a vine than a cactus. These peculiar plants are native to the rain forests of Central and South America, where they live high in the jungle canopy. They produce long, flattened, vine-like stems with a few tiny spines at the edges. Some varieties have distinctive zig-zag shaped stems. These interesting plants have become very popular because of their large, spectacular flowers in many brilliant colors. They are surprisingly easy to grow if their basic needs are met.
Select a location sheltered from strong winds, where your orchid cactus will receive bright filtered light to partial shade. Choose a humid, partially shaded place in extremely hot climates. Do not place an orchid cactus in full sun.
Place your orchid cactus in a sturdy hanger so its long stems can arc gracefully downward. Be sure there is enough room to accommodate the growing stems, which will eventually be quite large.
Water your orchid cactus once a week by filling the pot with water until it drains out the bottom. Wait long enough to allow the pot to stop draining and then fill the pot once more. Keep the soil evenly moist but do not let it become waterlogged.
Fertilize your orchid cactus with a balanced liquid plant food diluted to half the recommended strength once a month, during the summer while the plants are actively growing.
Re-pot your plant only when it has thoroughly outgrown its pot by placing it in a slightly larger new pot filled with rich, extremely well-drained potting soil. Allow your orchid cactus to become slightly root-bound because this will increase flower production.
Stimulate flowering by feeding your orchid cacti with an application of low nitrogen fertilizer, such as 5-10-5, once at the end of February and once again in early November. Do not give your cacti any fertilizer in the months of December or January.
Keep your orchid cactus in a place where nighttime temperatures are between 40 and 50 degrees F during the winter months to encourage the plant to set buds. Expect to see flowers appear on day flowering varieties from April to June.