Dave Robson

Flowering trees and shrubs can provide some enjoyment inside during the winter through forcing, something that any child or adult can do. In fact, forcing gives kids something to do on those days when they don't have anything to do.

Forcing is a process where you fool the plant into thinking conditions are springlike, even though it is the dead of winter. The process only requires a pair of pruning clippers, a bucket or large container, sunshine, a tub and water.

Most branches can be forced, though oaks, maples and sweet gums may not be all that impressive. You end up with green shoots and expanding leaves, which can be beautiful in their own right, but no colorful flowers.

The excitement of forcing comes from choosing flowering trees and shrubs.

Forsythia is an easy forcer. Branches only need a couple of weeks of dormancy, which has usually occurred by January.

Fruit trees such as apples, peaches, cherry, pears and quinces give successful results. These extra-early spring bloomers have a nice light fragrance as well as pale pink, red and white flowers.

Red Twig Dogwood, redbud, dogwood, crabapple, Chinese or Lacebark Elm, and many viburnums can be forced with few problems. Of course, don't forget the pussy willows.

Lilacs, while quite fragrant, are hard to force. The flower buds start to expand and then wither, possibly due to the lack of light, temperature or nutrients, or a combination of the three.

Choose branches with the largest buds. The bigger the bud, the quicker it will open. You might want to pop a bud off a limb and peel it open to see if it is green or white inside, indicating a live bud. Small buds may dry out before opening.

Cut branches in the early afternoon after the sap and temperatures have risen, preferably above freezing. If the temperatures are cooler, take care to avoid breaking off the frozen buds.

Prune selectively so the plant's shape isn't destroyed. Prune uniformly around and throughout the plant. Look for branches with interesting shapes, not just straight up and down switches. Avoid cutting everything off the top.

Once branches are cut, soak them for several hours or overnight in a bathtub filled with warm water. Make sure branches are submerged and branch ends are beneath the water. The warm water softens the flower buds and allows for easier forcing.

Also, tell people that you are soaking branches in the bathtub. Early morning risers may not appreciate discovering branches in the bathtub.

Cut another inch off the branches before placing the limbs in a bucket or large container of warm water. This aids in the quick uptake of water. Some florists have success with crushing the base of stems with a hammer. However, don't pound the stems.

Limbs produce the best flowers when placed in bright sunshine and cool temperatures. A southern exposure produces the best color. Unfortunately, it tends to be too warm. Ideal forcing temperatures are in the 55-65 degree range. This may be too cool for many people.

It can take two to three weeks for flowers to open. It won't happen overnight; the buds will slowly swell, expand and pop open.

The closer it is to spring, the faster the branches force into flower.

Check the water level daily and don't allow the limbs to dry out.

Once flower buds start to show color, place the limbs in a tall vase to enjoy throughout the house. Keep temperatures on the cool side for longevity.

Occasionally, limbs such as pussy willows will produce roots. Limbs can be transplanted outside in spring. However, growth isn't guaranteed. Many limbs will die due to lack of sufficient stored energy.

David Robson is an Extension Educator, Horticulture, at the Springfield Extension Center, Cooperative Extension Service, University of Illinois. You can write to Robson in care of Illinois Country Living, P.O. Box 3787, Springfield, IL 62708. Telephone: (217) 782-6515. E-Mail: robsond@idea.ag.uiuc.edu

16 ILLINOIS COUNTRY LIVING JANUARY 1998