The first step in growing amaryllis is to choose the correct size pot, which is one that is up to double the diameter of the bulb. A pot that is 5 inches to 7 inches wide is usually appropriate and provides the tight growing space the bulb needs to thrive, according to About.com.
For best results, plant amaryllis bulbs in the fall or early winter. Add a small amount of potting mix to the pot before inserting the bulb, and then place the mix around the bulb, leaving the top third of the bulb exposed. Growers should keep the soil moist at all times and should place the pot in a window that receives plenty of direct sunlight. Once there is no danger of frost, the amaryllis may be moved outside to a sunny location, according to the U.S. National Arboretum. The plants need fertilizer every two weeks.
Amaryllis bulbs go dormant in the fall. Growers should cut the stalk back to just above the bulb and bring the plant inside. To force the bulbs to bloom for the holidays, growers should cease fertilizing in August and stop watering about 10 to 12 weeks prior to the desired bloom date. Amaryllis bulbs bloom for several years if they receive the proper care.