Growing Fragrant Hyacinth Indoors
Hyacinths require a cooling period before they bloom. We can “force” a hyacinth to bloom by setting the bulb in a cool spot for 10–12 weeks. This mimics winter. You may be able to find bulbs which are pre-cooled, further reducing the cooling requirement by 2–4 weeks.
Look for hyacinth bulbs labeled for forcing. These are larger bulbs of cultivars that force easily.
You can plant them in potting soil. Hyacinths are most often grown in groups of 3 bulbs set in a 6-inch pot. Place them so the tip of each bulb is at the surface.
I encourage you to try growing hyacinths in water. Forcing vases are available at florist shops, garden centers and online. A deluxe vase is shown (see photo). The classic vase looks like an hourglass with its top cut off. Place the bulb in the top chamber and fill the bottom chamber with water so it stands about 1/4-inch from the base of the bulb. The bulb will rot if it sits in water.
During the cooling period, you can watch the bulb sprout its pure white roots. It’s absolutely fascinating!
Set the bulb in a dark, cool (approximately 40°F) place. A refrigerator or unheated garage works well. If set in a refrigerator, keep apples away because the fruits emit gas that inhibits flowering.
If planting in soil, you may need to water the bulbs once or twice during winter. If planting in water, check the water now and then; replace the water if it gets low or cloudy.
The plant will develop a strong root system and then sprout after 10 weeks. Once the plant has sprouted a couple inches, take it out of the dark and gradually introduce it to more light (bright but indirect) and warmer conditions (approximately 60°F).
Blooms will appear in 3–4 weeks. The fragrance is amazing!
Written by Tom Kalb, Extension Horticulturist, North Dakota State University. Published in the NDSU Yard & Garden Report, November 7, 2016. The photo was made available under a Creative Commons license specified by the photographer: Christina B Castro.