Known scientifically as Hippeastrum, amaryllis is a tropical bulbous plant cultivated for its large, trumpet-shaped flowers which bloom in vibrant shades of red, orange, white or pink. When grown indoors as a houseplant, amaryllis blooms for four to six weeks at a time, with each 8-inch blossom lasting approximately two weeks. With just a little bit of effort, amaryllis houseplants can be forced to bloom again and again.
Obtain firm and healthy-looking amaryllis bulbs from a nursery or garden centre; the larger the bulb, the larger the flowers. Select a planting container that is large enough to allow 2 inches of space between the base of the bulb and the sides of the pot and has two to three drainage holes in the bottom. Place 2 inches of coarse gravel inside the pot to facilitate healthy drainage and prevent it from tipping due to amaryllis' top-heavy flower stalks. Plant the bulb in well-draining potting mix with 2/3 of the bulb above the surface of the soil. Water the bulb thoroughly and place it in a cool, bright location until it sprouts.
Sunlight and Temperature
Amaryllis needs four hours of direct sunlight per day to produce the characteristic blooms. The Clemson University Cooperative Extension recommends placing amaryllis within 4 feet of a south- or east-facing window. Provide your amaryllis with 70 to 75 degree F temperatures until it starts to bloom. Move the blooming amaryllis to a location where it receives bright, indirect sunlight and lower the temperature to 18.3 degrees C to prolong the life of the blossoms.
Irrigation and Fertilization
Amaryllis requires consistently moist soil to bloom successfully. Water the amaryllis every 10 days to keep the potting mix slightly moistened until the plant flowers. When the plant starts to bloom, increase the frequency of irrigation to once every seven days. Amaryllis appreciates frequent fertilisation once it starts to grow and bloom; fertilise every other week with a water-soluble houseplant fertiliser, used according to package directions.
Amaryllis can be forced to reflower after it has completed its blooming cycle. Start by removing spent amaryllis blossoms from the plant with sharpened, sterilised garden shears; allow the foliage to wither and die. Move the amaryllis to a cool, semi-dark room that is kept between 10.0 and 12.7 degrees C for eight to 10 weeks; withhold water and fertiliser from the plant during this period. When your amaryllis presents new growth, remove the dead foliage, move it to its spot near the window and resume your regular watering schedule.