If your plant hasn’t bloomed for over a year, it may be just resting, or it may not be getting all of the required elements. Some expert gardeners are able to get African violets to bloom 10 months of the year. This is because the plants are given perfect growing conditions. More often, though, African violets will bloom for a few weeks, then rest for several weeks, and then bloom again. Here are some pointers on care:
Give the plants average household temperatures, but avoid drafts or sudden changes in temperature. Place the plants in a bright window, but keep them from getting direct sunlight. Keep the soil moist, but wait until the soil surface begins to dry before watering. Use tepid, not cold water, and try not to get water on the leaves or crowns of the plants when you apply water. African violets like humidity in the air. To increase humidity, place the pot on a tray of pebbles in which you keep about a half-inch of water. As the water evaporates, it will add humidity. Cut the flowers and stems off when the flowers fade. Feed them with a special African Violet fertilizer.
For more specifics about how avid hobby and professional growers care for their violets, you might enjoy the website for the African Violet Society of America.