The stalks can be 2 feet tall, the blooms as much as 8 inches across. Tie the flower stalk loosely to the stake. Do not allow the stake to touch the petals or bulb. Rotate the container to avoid a permanently leaning flower stalk. Heat initiates the amaryllis bloom, while light affects the quality of the bloom.
Bright light is good, but direct rays can lower the quality of the flowers.
Under good conditions, amaryllis flowers retain quality for about two weeks. Remove the flower stalk 2 inches above the neck of the bulb once the blooms have withered, but leave the straplike foliage to grow. You can continue to grow the holiday amaryllis in its container or transplant the bulb into the garden, with half of the bulb above the soil in a fertile, well-draining bed, ideally with morning sun and afternoon shade. Wait to leave amaryllis outdoors until April, when there is no threat of frost. Some gardeners simply sink the bulb, pot and all, into a raised bed.