Hyacinths are flowering plants in the asparagus family. They have bulbs and produce small clusters of flowers and are originally native to the eastern part of the Mediterranean Sea. These plants grow well both indoors and outside, but indoor hyacinths require special care. To care for indoor hyacinths, you should keep them in a location that is not too hot or cold, has just the right amount of humidity and does not receive direct sunlight. Choose soil that drains well but will remain moist, and be sure to plant the hyacinth bulb at the proper depth.
Common garden hyacinths are all members of the species Hyacinthus orientalis, a species that originally was cultivated in the Netherlands. They produce a cluster of leaves about 1 foot (30.5 cm) in length, with a spike of small flowers in the center. The color of the flowers depends on the variety of hyacinth. Some have white, pink, red, orange or yellow flowers. Others might be blue or purple.
Indoor hyacinths require a mild environment. Choose a location that is 50° to 75° Fahrenheit (10° to 24° Celsius). Keep your hyacinths away from heating vents, direct sunlight or other hot parts of the house. Provide moderate humidity; in the winter, you might need to place your plants near a humidifier.
Provide hyacinths with bright indirect sunlight, ideally from the east or west. Avoid placing these plants in a window or another area where they receive direct sunlight. Excessive sunlight can burn the flowers or leaves.
Choose a basic potting soil that drains well while retaining enough water to stay moist. Add peat moss, perlite or sand to aerate soils that pack easily. Plant the hyacinth bulb in a pot that is 4-5 inches (10.16-12.7 cm) deep, to a depth of twice the height of the bulb.
Indoor hyacinths grow best with infrequent, deep waterings. Drench the soil inside the pot with lukewarm to warm water, then allow it to dry slightly between waterings. Do not keep the soil wet or soggy, and avoid cold water. You can use rainwater to reduce the risk of damage from chlorine or other tap water chemicals, but rainwater is often acidic. Adjust the potenz hydrogen (pH) level of your hyacinth's soil accordingly by using lime or other soil additives.
Hyacinths that are grown indoors are at risk of bulb rot, especially if they are kept very warm and wet. Bulb rot can cause the leaves to yellow and wilt. It might even cause the leaves to fall off entirely. Inspect the bulb carefully for evidence of rot or pest damage when re-potting your hyacinth.
Like their outdoor cousins, indoor hyacinths reproduce by creating offsets on the side of the original bulb. These tiny bulblets produce the same types of hyacinths as the parent plant and are almost genetically identical. Unlike outdoor plants, indoor hyacinths can produce offsets at any time.
To propagate this plant, remove the bulblets during a period when the hyacinth is dormant, or not producing new growth. Place them in a 3-inch (8-cm) pot that has been filled with moist fiber. Keep the pot in a cool, dark place for about 10 weeks, watering when the fiber feels dry.