The spring blooming season is just around the corner. Within a few weeks, we’ll start seeing beautiful color gracing our gardens, borders and landscapes.
But have you ever considered forcing spring-blooming bulbs indoors and offering them to your customers during the winter? Providing customers with spring freshness in the middle of winter—especially on Valentine’s Day—will set you apart from other flower farmers. So let me explain a bit about forcing bulbs indoors so you’ll be ready to do it next winter. Of course, you’ll want to do more research, but here are the basics.
When we talk about “forcing” bulbs, we’re actually talking about tricking bulbs into thinking it’s spring and time to bloom.
There are several things to consider when forcing bulbs: which bulbs to force, whether the bulbs require a chilling period, how long the chilling period should last and how cold the chilling environment should be.
Among the most popular bulbs to force indoors are crocus, daffodils, hyacinths and tulips. Some bulbs, like hyacinths, don’t require soil—a little water and some pebbles makes them very happy. My go-to source for bulbs is K. van Bourgondien—they offer a phenomenal selection of high-quality bulbs that you can force indoors.
Forced bulbs are divided into two groups: those that require a chilling period and those that don’t.
What I mean by chilling is the storage of bulbs in a cold frame, a cold basement or a refrigerator that is not used to store food. Here at the farm, we use a small cooler for individual bulbs. Bulbs that are already planted in pots and containers are placed in a cold high tunnel, which has more space.
To encourage a good root system for bulbs in containers and planters, we try to keep the temp around 40°F. Then we lower the temperature even further for the remainder of the cooling period. Different bulbs require chilling periods of different lengths. For example, tulips require a longer cooling period and crocus a shorter one.
I like to leave bulbs in cool storage as long as possible to time the season just right. Most bulbs will tolerate extra chilling, which will allow a succession of winter blooms. When brought out of the cold, the bulbs will typically bloom 2-5 weeks later. So, planning is crucial if you want bulbs to be blooming around Valentine’s Day.
Whatever you do, don’t judge a bulb’s readiness for removal from cool storage by the appearance of green shoots. Instead, check the bulb’s root system. For example, look to see if roots are emerging from the container’s drainage holes. Or slightly lift the bulb to see if a good root ball has formed. Without roots, your spring bulbs won’t flower correctly.
So, there you have it—the basics of forcing bulbs indoors. Just be sure to do your research before you start because chilling periods and other requirements will vary by variety.
Forcing bulbs may sound like a lot of work, and it does take time and effort. But let me assure you, it’s all worthwhile. The reward is a bountiful season of buds and blooms during the cold, dark days of winter.
Happy Gardening!
Pamela Anthony
Beehind Thyme Farm & Garden