Narcissus is the classic spring-flowering bulb. For many people, the appearance of these delicate flowers outside signals the end of winter and the beginning of spring. Indoor gardeners can enjoy Narcissus too. They are generally less than a foot (30 cm) in height and bought already in bloom in decorative pots. Like other spring-flowering bulbs, Narcissus can be forced to bloom but will require a chilling period of about 12 weeks.
Light: For established plants, place them in bright light as on an east or south windowsill. Bulbs that have not sprouted should be kept away from direct sunlight until new growth emerges, and the plants are established.
Water: Many people start Narcissus from bulbs. If you're doing this, plant the bulbs in moist potting media with the pointed end facing up. Keep the soil continuously moist, but not soaking. They can also be grown directly in stones or gravel by suspending or anchoring the bulbs in the substrate and adding just enough water to reach the base of the bulb. In all cases, it's crucial to avoid letting the body of the bulb become saturated or sit in water–it will quickly rot. New growth should emerge within a few days to a few weeks after planting, depending on the temperature. The bloom should follow in 4-6 weeks.
Temperature: Cooler (around 65ºF/18ºC).
Soil: Bulbs can be planted in regular potting soil or pebbles or clay. The key is to keep the balance of moisture right: they should have constant moisture, but never be soaked.
Fertilizer: During the growing period, use weak liquid fertilizer weekly. Young plants shouldn't require fertilizer as they will draw all their nutrition from the bulb itself.
Like other bulbs, Narcissus multiply by putting out new bulbs and forming a clump. However, as with other indoor bulbs, most people discard the plant after bloom or transplant it outside. Offsets aren't as vigorous as their parents, and old bulbs will never bloom again indoors.
Usually not necessary, as the most common indoor Narcissus (Paperwhite) are sold in decorative pots or as planting kits that are designed to be discarded after the 3-week bloom is over. If you do want to save the bulbs, treat like other bulbs: after the bloom is over and the plant has died back, dig up the bulb, dry and clean it, and store it in a paper bag or container in a cool, dark place until the next spring.
The Paperwhite Narcissus are frequently sold as blooming kits. These are a great way to get started with bulbs. They don't require a chilling period and bloom readily with a pot of tall, fragrant flowers. The plants may need staking to remain upright as indoor plants frequently become top-heavy in small containers and want to tip over. You can prop them up with bamboo stakes.