Thanksgiving cactus is a winter-flowering houseplant native to Brazil, which comes in a wide array of colors including red, purple, oranges, pinks and whites although reds, whites and pinks are the most common. When planted in a decorative pot, Thanksgiving cacti make a wonderful holiday table centerpiece, or as a gift for friends and family.
Thanksgiving cactus grows well in light shaded areas. They prefer an evenly moist soil although they can tolerate dry conditions. So, do not allow the soil become waterlogged, especially during the dark days of winter. Do not let the soil dry out either. Reduce watering from fall through spring. Fertilize plants monthly from the time new growth starts in late winter or early spring, and throughout the summer using a one-quarter strength soluble fertilizer. Reduce fertilizer during the fall and early winter. The Thanksgiving cactus flowers best when kept somewhat potbound. Repotting is necessary only about once in three years. The potting media must be well-drained with good aeration, because the plant does not grow well in heavy, wet mixes. A good mix may contain one part potting soil, two parts peat moss and one part sharp sand or perlite.
They do not tolerate frost and hence they need special care during the frosting months when they should be brought indoors. For these cacti to form buds, during mid-September, these cacti will need 12 to 14 hours of total darkness along with cool nighttime temperatures. The easiest way to achieve this is to place the plant in a closet from dusk to dawn. Or you can cover it with a large brown paper bag. If you keep the plant in a cool room (around 50 degrees F 24 hours a day) in September and October, chances are excellent that it will produce flowers, regardless of day length.