Prepared hyacinths bulbs are those that have received a chilling treatment which imitates winter. These bulbs still need to be kept cool and in the dark for another 8 weeks or so, but prepared bulbs are eager to flower much sooner. One of the earliest varieties to bloom,Hyacinth Anne Marie has cherry blossom pink florets to soften those gray winter days. Other prepared varieties include the bright rich red of Jan Bos, snow white L’Innocence, and of course, the ever-popular Delft Blue.
To bring a hyacinth on glass into bloom, fill the lower portion of a forcing vase with water and set the bulb over it. Place the rooting side down just over the water, but keep the base of the bulb dry. Only a few millimeters away, the water and moisture below the bulb is enough to encourage roots to grow down into the vase.
Set your hyacinth on glass in a cool and dark place, with temperatures of 7-12°C (45-55°F) and good air circulation, for about 8-13 weeks. Basements and garages often provide these ideal conditions. Check on the bulb and vase once a week to ensure the water level is where it should be, just below the bulb, and that roots are developing. When necessary add a little more water to the vase. Replace cloudy water by tipping out the liquid, and then refill the vase with fresh water at room temperature.