Victorians grew cyclamen with great success, but their achievement is most likely due to their cool, drafty houses -- an optimal condition for these tuberous perennials. Cyclamen thrive in temperatures ranging from 55 to 65 degrees, so it's best to put them on a cool windowsill with indirect light in an unheated room or cool greenhouse. If the leaves start to yellow, the room is probably too warm; move the plant to a cooler spot.
Cyclamen prefer a humid environment. If you don't have a greenhouse, place the pot on a tray of pebbles and fill it with water to the level of the pebbles. The water will evaporate, creating humidity around the plant.
Although cyclamen benefit from humid conditions, overwatering can kill them. They are grown from tubers that will rot if they are watered too heavily, so never pour water directly on the tuber. Also, like African violets and gloxinia, cyclamen prefer not to have water poured on their leaves. Always use a watering can with a long, thin spout, and water along the side of the pot. Or avoid the leaves altogether by immersing the bottom three-quarters of the pot in a basin or sink filled with water. Keep the pot immersed until the surface of the soil glistens, no longer than 10 minutes. Cyclamen also need to be fed a standard-strength fertilizer every 2 weeks. Under these conditions, cyclamen will bloom for several months.
After the cyclamen has flowered, twist off the flowering stems, and discard. It's better to twist than to use scissors because the stems come off completely at the base instead of leaving a stub that could rot. In order to bloom the following year, cyclamen need a winter rest. Treat yours as you would an amaryllis: Stop feeding it, and slowly reduce watering. Allow the plant to dry out completely. When the soil is dry and the foliage has shriveled, place the pot on its side (to prevent moisture or humidity from reaching the plant) in a cool place (such as a basement or garage). In midsummer, repot using fresh soil and the same size pot.