Nothing says spring like a colorful bed of tulips or daffodils. That's true even in warm climates, where winters are mild and there's rarely a frost.
But spring-blooming bulbs are native to cold climates, and if the bulbs aren't exposed to a few months of wintery temperatures, the flowers don't develop properly. Gardeners in zones 8-10 need to trick these bulbs into blooming by putting them through an artificial winter before they get planted.
This chilling period means keeping the bulbs at 35 to 45°F for between 12 and 20 weeks. The length of time depends on the type of flower bulb. Cold temperatures cause a bio-chemical response inside the bulb that “turns on” flower formation and initiates root growth. Without a chilling period, the bulbs may try to bloom, but their stems will be short and the blossoms malformed.
If you live in zones 8-10, the best time to start chilling your spring bulbs is in the fall, right after you receive them. To learn more about pre-chilling bulbs and which ones work best, read our new article: How to Grow Spring Bulbs in Warm Climates.