Garden calendar: For the week of Dec. 9
Caring for your Amaryllis (Hippeastrum) bulb: Amaryllis bulbs make wonderful holiday gifts. They are tender bulb plants native to South America, that typically bloom before the long leathery leaves appear. Amaryllis were first “found” in 1828 by Eduard Frederick Poepping, a physician on a plant hunting expedition in Chile. More than 70 species of these plants exist in the wild. However, Dutch, South African or Israeli hybrid plants bred for larger flowers and sturdier stems are more common in commerce. The common name “Amaryllis” is something of a misnomer; true amaryllis or belladonna lilies are from South Africa. The botanical name, Hippeastrum, is the correct term and should be used to avoid confusion.
Hippeastrum bulbs are usually sold as a dormant bulb, sometimes packaged with a planting kit. If the bulb is un-potted, purchase a 6-8” “bulb” or “azalea” pot that is about two inches in diameter larger than the bulb diameter. For dwarf Hippeastrum choose a smaller size pot. Use a well-drained houseplant mix that does not contain pine bark and plant the bulb so about one-half protrudes above the soil line. The soil line should be about one inch below the rim of the pot to accommodate watering. After the soil is gently firmed around the bulb, water it thoroughly.
Hippeastrum bulbs generally grow one-half inch to an inch in diameter each year. They like to be slightly pot-bound, but will need repotting every few years. Put it in a sunny room or window where temperatures ideally range between 65-70 degrees while the flower stalk is being produced. If the temperature is too high, a weak flower stalk and smaller flower may result. Keep the soil slightly moist, but do not overwater as this can cause the bulb to rot. The plant will use more water once roots are established.
Fertilize Hippeastrum once a month with a 5-10-10 or 10-10-10 fertilizer, as good fertility is essential for high quality blooms. Follow label directions and apply fertilizer at the rate directed for houseplants. Six to eight weeks after planting, the bulb should begin to flower. You can extend its bloom by taking the plant out of direct sunlight and placing it in a room where temperatures are cooler—about 60-65 degrees. Two to six big, beautiful white, red, salmon, or pink flowers are produced on a stalk that may be 18-24” tall. Some Hippeastrum cultivars are bicolored, such as “Apple Blossom,” a lovely pink and white cultivar.
As each flower fades, remove it, taking care not to damage the main flowering stem. When the flower stalk droops and starts to turn brown, it can be cut off a couple of inches above the bulb neck. By now, leaves should be present, so it is time to encourage the plant to grow. Move it back to a sunny warm window or outside for the summer, once the danger of frost has passed. Keep it watered and fertilized while leaves are actively growing — they are producing food resources for next year’s flowers.
If you decide to put your plant outside for the summer, you may sink the pot into the ground in a lightly shaded area with an east or west exposure or keep the pot above ground, but realize it will need water more frequently. In mid to late August typically, the leaves will die back. Bring the plant back inside before there is any danger of frost.
By September, if not earlier, Hippeastrum bulbs will enter dormancy. Remove the brown, dried leaves and store the plant in a cool dry place where the temperature is between 45-55 degrees if possible. Keep the bulb on the dry side but don’t let it completely dry out. Withhold water while the bulb is dormant.
Hippeastrum bulbs require 8-10 weeks of dormancy in order to initiate flowering. By late October or November growth will begin again, and you can look forward to another set of beautiful long-lasting flowers!