Amaryllises are subtropical perennial flowering bulbs that thrive in temperate climates. With their majestic blooms and tall elegant growth habit they are desirable as garden bedding plants as well as indoor or outdoor container-grown specimens. They prefer temperatures that hover around 70 degrees F and can be overwintered indoors in cooler climes.
For outdoor amaryllises, cut off the spent flower stalk down to the base of the stem just two inches above the bulb top. This will make way for a second bloom stalk if applicable. Leave the foliage in place to recharge the bulb with nutrients and moisture.
Cease feeding in September and scale back watering to keep the soil just barely moist. Cut off any top foliage only after it turns brown and desiccates.
Mulch around or over the amaryllis bulb planting with 2 to 3 inches of organic mulch such as compost, shredded bark or cocoa bean hulls. The mulch will protect the bulb from cool temperatures, hold moisture in the soil and keep weeds from settling.
Prepare a container-grown amaryllis for winter by ceasing fertilizing and watering in the fall. Cut off all of the top foliage when it subsequently dies back. Place the pot in a dry location with low light and ambient temperatures between 65 and 75 degrees F until early the following year. In mid to late January move the pot back into a sunny location and resume watering and feeding. The growth and flowering cycle should resume within two months time.