Amaryllis bulbs are grown in bright indirect sunlight and soil with a large amount of sand content. The plant is often started indoors in a clay pot. Amaryllis bulbs are planted in nutrient-dense soil, and sometimes fertilizer is added to encourage growth and prolonged blooming of the flowers. As the shoot matures, it can be held up with a wooden stake, as the flower can get heavy and the stem is relatively thin and flimsy. Also, bone meal or superphosphate can be purchased to fertilize the plant and add the essential nutrient, phosphorus.
Choose amaryllis bulbs that have no signs of visible damage, and plant a single bulb in the clay pot with the soil amended with the bone meal or superphosphate. Be sure to leave 2 inches (5.08 cm) of space between the edge of the clay pot and the amaryllis bulbs, and leave half of the upper portion of the bulb uncovered. Also, only fill the pot partly full with soil, which will allow for ample watering of the plant. Next, gently press the soil and the bulb down to ensure the soil is lightly compressed and the bulb is set. Light, rather than heavy, compression will help prevent toppling as the plant matures.
For the initial watering, soak the whole pot in water, in a sink, bathtub, or other large shallow container. Wait until the pot stops bubbling before removing it, as this will ensure that the roots have been adequately watered. From this point on, be sure to keep the soil moist, but not oversaturated, to prevent rotting of the roots. Finally, place the pot in an area of bright, indirect sunlight, and growth should be seen in as little as one to two weeks.
As the plant grows, the flowers will begin to bloom atop of the stems as they become more robust. Amaryllis will often grow to 2 feet (0.6 m) in height. The leaves begin at the base of the bulb and fan out from the base of the stem. A white, fleshy substance surrounds and protects the amaryllis bulb and provides food for the plant to thrive. This inherent food source makes regular fertilizing usually unnecessary.
When transferring an amaryllis plant to an outdoor setting, it is important to keep the whole of the root system intact. This is especially important for the amaryllis plant because some nutrients are actually stored within the root system. The bulbs should be harvested before the first frost of winter to ensure their survival.