Winter Activities: Pruning and Forcing Early Blooms
The dormant period is a great time to get other gardening activities out of the way. Towards late winter, for example, you can consider forcing flowering branches ahead of schedule. The trick here is to mimic spring when the buds bloom. Some spring-flowering plants that respond well to forcing include forsythia, witch-hazel, honeysuckle, and at a later date—about six weeks before outdoor flowering time—try magnolias and flowering quinces.
Try this activity on a sunny day when the mercury rises above freezing. You’ll need a pair of sharp, bypass pruners and a container for your stems, which should ideal hold water mixed with a floral preservative. Choose young branches that are already swelling with flower buds (these are fatter and larger than leaf buds). Using sharp pruners, cut the sprays flush with a major branch. You should also consider shaping your shrub while you work.
Pruning is best done in the dormant season since the plant’s stored food reserves are least affected and cuts made to the plant close rapidly. It is also easy to see the basic structure of the plant and determine which branches to thin. Pruning encourages new wood to form. As you remove old stems, younger and more productive shoots will soon take its place. Keep this in mind and avoid pruning in the late summer or early autumn, since this can encourage the growth of new shoots that might not survive colder temperatures once winter sets in.
When pruning, use thinning cuts to reduce the size of a shrub without changing its natural branching structure. Take great care to make the right cut when pruning a branch back to a bud. The incorrect cut will cause an inward-facing bud to grow on an outward facing branch and will tangle with other branches. As you choose sprays for early blooms, cut each stem above an outward-facing bud.
Bring the branches indoors. Choose a nice room where the temperature can be kept between 60F and 70F. Higher temperatures can speed up the forced blooms but they can also diminish flower size and color.
Recut the branches on a slant just above the original cut and peel back about an inch of bark. You can also choose to mash the ends very lightly with a hammer. Both methods aid the stems’ water intake. Remove any remaining foliage from lower third of branch, and place the stripped stems into the container of tepid water and floral preservative.
Care for your new stems by changing the water often and misting the branches daily. Keep them out of direct sunlight from now. You’ll want to do this to fool the branches into thinking that the cool rainy days of spring have already arrived. Should you want to try speeding up the process, marthastewart.com suggests putting a plastic garbage bag over the tops of the branches and lifting them when it is time to mist. Remove them once the buds begin to flower.
When the buds begin to swell, you can move the branches to a vase and move to a well-lit room, but never in direct sun. They will blossom two to three weeks after cutting and will keep for about a week.
As the days pass you may find roots growing on your branches after they have finished blossoming. If you want to plant these, continue to change the water and add a pinch of 10-10-10 soluble plant food, until the roots show ¼ inch in length. Keep pruning the branches to roughly 6 inches. Then bury each rooted portion in a small pot filled with a good potting soil mix. Keep them moist for several weeks and wait until the weather warms before you take the pot outdoors. Avoid planting them on the ground, taking care to shelter them for the first two winters. Only when they are sturdy enough can these be planted on the ground.