Forcing bulbs inside is a super easy technique that’s simply a sleight of hand—a trickster’s way to get blooms by faking out your flowers about what season it really is. It involves very little effort and few materials. The biggest exertion? Scheduling their arrival.
Chilling Bulbs
Here’s the deal: Bulbs that grow indoors sometimes need a reminder that they’ve been through winter—however fake it is. In fact, all bulbs except amaryllis and paperwhites need a cold snap. What makes those two different? They don’t get cold at home in their native tropics, so they don’t need winter wherever you live. For other flower bulbs, though, you’ll have to chill them a little to get them to bloom inside; just how long depends on the bulb. Generally:
Chill in September, bloom in JanuaryChill in October, bloom in FebruaryChill in November, bloom in MarchChill in December, bloom in April
Amaryllis
Chill time: None Bloom time: 6-8 weeks
Crocus
Chill time: 8-15 weeks Bloom time: 2-3 weeks to bloom after chilling
Daffodil
Chill time: 2-3 weeks Bloom time: 2-3 weeks to bloom after chilling
Grape hyacinth
Chill time: 8-15 weeks Bloom time: 2-3 weeks to bloom after chilling
Hyacinth
Chill time: 12-15 weeks Bloom time: 2-3 weeks to bloom after chilling
Iris
Chill time: 13-15 weeks Bloom time: 2-3 weeks to bloom after chilling
Paperwhite
Chill time: None Bloom time: 3-5 weeks
Snowdrop
Chill time: 15 weeks Bloom time: 2 weeks to bloom after chilling
Tulip
Chill time: 10-16 weeks Bloom time: 2-3 weeks to bloom after chilling
Forcing Chilled Bulbs
Choose a pot deep enough that you have a couple of inches below the bottoms of the bulbs for soil and roots but that is tall enough you can cover the bulbs up to the necks. Fill the bottom of the container with potting soil. Use enough bulbs to fill the container. You can crowd them or give them some air. Cover with potting soil just to the necks of the bulbs. Chill the bulbs for the recommended time period. The crisper drawer of your refrigerator is just fine for a handful of bulbs. An unheated basement, cold space, or inside a cold frame also works as a cool spot to keep your bulbs. Keep the soil just damp—not wet. Start waking up your bulbs by giving them a few weeks of warmer (but not too warm) temps and some indirect sunlight. Once the bulbs shoot up and are a couple inches tall, give them more sun and a warmer spot.
Forcing Bulbs That Aren’t Chilled
Soak the roots of the bulbs in a shallow pan of lukewarm water for a few hours.Fill a pot with potting soil or garden pebbles; insert the bulbs but leave the top two-thirds exposed.Gently tamp down the soil or pebbles around the bulbs. Water until damp, then place in a sunny, warm spot.
