Every gardener can enjoy spring blooms a little earlier than usual, the trick is to do so indoors. Many of our ornamental flowering trees and shrubs have the 2022 flower buds ready and waiting right now. Typically, our ornamental landscape plants produce the next season’s bloom not too long after they have completed flowering, so a few weeks after blooms fade, those landscape plants are already hard at work producing the next spring’s flower buds.
Why forcing blooms works
Outside in your yard, as the temperatures begin to moderate and we start to get rains or the air is full of moisture, the bud scales protecting the flower blooms slowly begin to soften and loosen. About this same time, sap flow begins. If gardeners continue to observe their favorite landscape tree or shrub, they will begin to see the buds swell in size. This is yet another indicator that spring is on the way.
As a gardener takes to the yard to do that early spring pruning, those branch clippings could be brought indoors and if there are flower buds, they could be “forced” to bloom for your enjoyment. It may take as little as a week or up to three or four weeks, depending on the plant and stage. By then, some of our earliest bloomers may be starting outdoors in the yard to continue the bloom show.
How to force blooms
To force a flowering branch to bloom indoors, the best tactic is to remember that in nature, the bud scales protecting the flower bud naturally soften allowing the flower bud to emerge as easily and quickly as possible. Inside, gardeners can wrap the branches in moist materials that are readily available like old rags or paper towels, just about anything that will keep the bud scales moist and softening. This should be done on the cooler side of temperatures, such as in the garage, a three-season room, or a semi-heated breezeway. Once those bud scales soften then warmer temperatures will allow the flower buds to expand and the bud scales will slough off.
Gardeners can start the forcing process over and over again, providing a succession of bloom, using new clippings each time. Gardeners can experiment with more than one kind of flower at the same time or keep them separate for a larger more impactful display.
What branches work
Ornamentals like forsythia and Amelanchier will take about a week to force, and redbuds, privet, and pussy willow, about two weeks. Honeysuckle, flowering almond, and slender deutzia will take about three weeks to force. Lilac, spirea, and crabapple will take about four weeks. The closer you are to their natural bloom cycle, the quicker they are for you. If your concern is taking away from the outside bloom show, then take your clippings from the back side or the side you do not see.
Once the blooms fade or you have more coming on that look a lot fresher, those branches and twigs can be added to the compost pile and then you are really recycling!
About the author: Richard Hentschel’s expertise extends across several subject areas with specialties in lawn care, fruit tree production, woody ornamentals, and home and community gardening. During his 45-year career in horticulture and agriculture, Hentschel became a well-known and respected expert for commercial and homeowner audiences, industry organizations, and media. He retired from University of Illinois Extension in April 2022 with nearly 30 years of service as a Horticulture Specialist and Educator in northern Illinois.