Forcing Bulbs - Prechilling Chart

Many spring flowering bulbs can be forced into bloom during the winter. Tropical bulbs, like paper whites, don’t require much more effort than potting them in soil or water. However, non-tropical bulbs, that are traditionally planted in the fall, need a period of cold temperatures to stimulate growth and flower production. This cold or chilling period should take place at a temperature of around 35 - 45 degrees F.

Almost any bulb can be forced, but below are some good choices for winter forcing and the chilling periods required. Forcing Flowering Bulbs for Winter Color has more detailed information about forcing bulbs.

Choice Cultivars for Winter Forcing of Spring Bulbs