By Richard Jauron, Greg Wallace
Believe it or not, the holiday season is just around the corner. One of the best parts of any good holiday celebration is beautiful holiday plants, including the spectacular amaryllis. What is the best way to ensure it will bloom for Christmas, and can it be saved afterward?
Here are some tips from Iowa State University Extension and Outreach horticulturists on how to handle amaryllis this holiday season. To have additional questions answered, contact the ISU Hortline at 515-294-3108 or hortline@iastate.edu.
When should I plant an amaryllis bulb to have it in bloom at Christmas?
An amaryllis bulb usually blooms about six to eight weeks after planting. Plant the amaryllis bulb in early November for spectacular blooms at Christmas. To increase the odds of having an amaryllis in bloom at Christmas, pot up one amaryllis bulb in early November and a second one several days later.
How do I pot up an amaryllis bulb?
Amaryllis bulbs can be purchased pre-planted in pots or unplanted. When purchasing unplanted amaryllis bulbs, select large, solid bulbs. The largest bulbs often produce two flower stalks. Gardeners can choose from single-flowering, double-flowering and miniature cultivars. Flower colors include red, pink, orange, salmon, white and bicolors.
When planting an amaryllis bulb, select a pot that is approximately 1 to 2 inches wider than the diameter of the bulb. The container may be clay, ceramic or plastic, but should have drainage holes in the bottom. Plant the bulb in a well-drained potting soil. Add a small amount of potting soil in the bottom of the pot.
Center the bulb in the middle of the pot. Then add additional potting soil, firming it around the roots and bulb. When finished potting, the upper one-half of the bulb should remain above the soil surface. Also, leave about 1 inch between the soil surface and the pot’s rim. Then water well and place in a warm (70 to 75 degree Fahrenheit) location.
Check the pot before watering a pre-planted amaryllis bulb. If the container doesn’t have drainage holes, remove the bulb and replant it in a pot with drainage holes. Water well.
After the initial watering, allow the soil to dry somewhat before watering again. Keep the soil moist, but not wet. When growth appears, move the plant to a sunny window and apply a dilute fertilizer solution every two to four weeks.
During flower stalk elongation, turn the pot each day to keep the flower stalk growing straight. Flower stalks that lean badly will need to be staked. When the amaryllis begins to bloom, move the plant to a slightly cooler (65 to 70 F) location that doesn’t receive direct sun to prolong the life of the flowers.
What should I do with my amaryllis after it’s done blooming?
Some individuals discard their amaryllis after it’s done blooming. However, if given proper care, it’s possible to save the amaryllis and force it to flower again next winter.
Proper cultural practices must be followed to successfully grow and reflower amaryllis bulbs. After the flowers fade, cut off the flower stalk with a sharp knife. Make the cut 1 to 2 inches above the bulb. Don’t damage the foliage. For the bulb to bloom again next season, the plant must replenish its depleted food reserves. The strap-like leaves manufacture food for the plant. Place the plant in a sunny window and water when the soil surface is nearly dry. Fertilize every two to four weeks with a dilute fertilizer solution.
The amaryllis can be moved outdoors in late May. Harden or acclimate the plant to the outdoors by initially placing it in a shady, protected area. After two or three days, gradually expose the amaryllis to longer periods of direct sun. The amaryllis should be properly hardened in seven to 10 days. Once hardened, select a site in partial to full sun. Dig a hole and set the pot into the ground. Outdoors, continue to water the plant during dry weather. Also, continue to fertilize the amaryllis once or twice a month through July. Bring the plant indoors in mid-September. Plants left indoors should be kept in a sunny window.
To bloom, amaryllis bulbs must be exposed to temperatures of 50 to 55 F for a minimum of eight to 10 weeks. This can be accomplished by inducing the plant to go dormant and then storing the dormant bulb at a temperature of 50 to 55 F. To induce dormancy, place the plant in a cool, semi-dark location in late September and withhold water. Cut off the foliage when the leaves turn brown. Then place the dormant bulb in a 50 to 55 F location for at least eight to 10 weeks.
After the cool requirement has been met, start the growth cycle again by watering the bulb and placing it in a well-lit, 70 to 75 F location. Keep the potting soil moist, but not wet, until growth appears. The other option is to place the plant in a well-lit, 50 to 55 F location in fall. Maintain the amaryllis as a green plant from fall to mid-winter. After the cool requirement has been met, move the plant to a warmer (70 to 75 F) location.