Place approximately 4 inches of river stones in a glass container 8 inches wide and 12 inches tall.
Examine the amaryllis bulb to find any roots extending from the bottom that are brown and dry. Cut off these roots without disturbing the white healthy roots.
Set the bulb on the river stones with the roots facing down. Add river stones around the sides of the bulb until only the upper 1/3 of the bulb is uncovered.
Add water to the container until the water level is 1 inch below the top of the amaryllis bulb. Do not submerge the amaryllis bulb--this will cause decay.
Place the container in a location that receives direct sunlight and stays at a temperature between 70 and 80 degrees F. Replenish the water every day as it evaporates so that it stays at the same level.
Watch for an amaryllis shoot to emerge in two to eight weeks. When the amaryllis blooms, rotate the container 90 degrees every day or two so that the bloom grows straight.
Discard the bulb when the blossoms wilt. Amaryllis bulbs grown in water do not generally grow well in subsequent plantings.