Back in the fall, your amaryllis bulb was pushed into dormancy by withholding all watering. In the weeks that followed, the foliage turned yellow and withered. You cleaned off the dried leaves and stored the potted bulb at 34 to 42 °F for the winter, not allowing it to freeze.
After a minimum of eight weeks, preferably longer, has passed, re-start the dormant potted amaryllis by simply adding water. Soak the pot in a trough of warm water for 2-3 hours. For large pots the bathroom tub or kitchen sink will suffice. If several dormant amaryllis bulbs have been stored away, start up one or more weekly to stagger the blooming period. Set the plant in a grow room or a sunny window and water as needed. Rotate the plant every 5-6 days so the emerging amaryllis does not lean (grow) toward the window.
After 6-8 weeks, the flower stalks and some leaves have emerged and stand tall. Usually 3-4 flower buds form on each floral stalk. Several stalks may shoot up, depending on the bulb size and vigor. Fertilize bi-weekly with a water soluble plant food such as Schultz®, Miracle-Gro®, or Daniels® according to package directions (for house plants).
The glorious trumpet shaped flowers bloom for 2-3 weeks and several flower colors are available. After the danger of spring frost has passed in your area, put the plant(s) outdoors on a sunny deck or patio for the summer.
Repeat the dormancy cycle again in the fall when the plant is scheduled to be brought indoors.