The exotic appearance of a blooming amaryllis is deceiving, because they're surprisingly easy to plant, grow and maintain. There's no reason that even beginning gardeners can't enjoy the stunning beauty of amaryllis. The most important single thing that you can do to assure success is to choose amaryllis bulbs wisely. Purchase large, plump bulbs with basal roots intact from a reputable retailer for best results. You can expect to pay a little extra for the more exotic striped, bicolor and other fancy varieties. Planting your amaryllis from October to late April will give you a breathtaking 7 to 10 week display from late December through late June.
Soak the roots and base of your amaryllis bulb in a shallow bowl of lukewarm water for several hours when you're ready to plant it. Replace the warm water whenever it cools. If you're not able to plant the bulb as soon as you get it, you'll need to store it in a cool, dark location at about 50 degrees F.
Partially fill a 6-inch clay pot, which will allow for best drainage, with good potting compost. Set the base of the bulb onto the soil, and stand a ¼-inch dowel rod next to it. Mature amaryllis blooms are very heavy and often require support to avoid breaking the stems. Positioning the stake now will prevent potentially damaging the bulb or roots later on. Plant the bulb up to its neck right alongside the dowel, being very careful not to damage any of the roots. Gently press the soil firmly around the bulb as you secure it into place.
Water the bulb enough to moisten the soil, but not so much that it's wet or soggy. Set the pot in a warm location with plenty of bright indirect light, such as a windowsill. The plant will need the temperature maintained at about 68 to 70 degrees F for stem development.
Water sparingly to avoid rotting the bulb until the appearance of the stem within a few weeks, keeping the soil just barely moist. Gradually increase the amount of water as the leaves and bud develop, keeping the soil uniformly moist, but not soggy. Your amaryllis plant will begin to grow very quickly at this point, and flower about 7 to 10 weeks after planting the bulb.
Give the pot a quarter turn every other day to encourage straight, upright growth of the stem. Once buds begin to form, fertilize it with half strength water soluble flowering plant food every 3 to 5 days throughout the growing season. If the stem begins to sag or droop, secure it loosely to the stake with a thin strip of very soft cotton cloth.
Cut the spent flowers from the stem at the end of the blooming period. When it begins to sag, cut the stem back to just above the bulb. Keep watering and fertilizing the amaryllis for the next 6 months to promote development and growth of the plant's leaves. When they begin to turn yellow in early fall, cut them back to 2 or 3 inches above the bulb and lift from the pot.
Rinse any remaining soil from the bulb and its roots. Allow it to air dry for a couple of hours and put it in a dark, cool location to store at about 40 to 50 degrees F for at least 6 weeks. The crisper of your refrigerator is perfect for this, but make sure that you never store any apples in the appliance while your bulb is in there. Apples will sterilize the amaryllis.
Repot your amaryllis bulb anytime you wish, as long as it has been allowed to rest in the refrigerator for at least 6 weeks. The plant will spring back to life and bloom again in about 8 weeks.