Those freezing days during December, when temperatures in Seattle hit the low 20s, might have affected your trees and shrubs, particularly...

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Those freezing days during December, when temperatures in Seattle hit the low 20s, might have affected your trees and shrubs, particularly if you live at higher elevations.

To find effects of freeze damage, take a walk around the landscape.

Look at swelling buds on camellias, at the tips of tender plants like escallonia and at newly planted evergreens. Freezing temperatures may have nipped buds, leaving them brownish and softened. Dead branches will show crinkled bark or snap crisply off when bent.

You can gently stroke a branch with the clipper blade to look for live tissue; by removing only about a half-inch of outer bark, with just the slightest scrape, you’ll be able to see if the live green cambium tissue persists underneath.

If so, you’ll know the branch has little or no damage. If the frozen spots are limited, such as just a few exposed outer branches, prune out the damage down to healthy wood.

Dead wood will also look grayer than live wood, and will lack leaves or have dead leaves if it’s a broadleaf evergreen like English laurel (Prunus laurocerasus). If the plant is a Japanese maple or other deciduous ornamental, all the leaves should have fallen by now.

If dead leaves stay on a branch, while others around it have lost leaves normally, check the branch for damage. Dropping leaves in fall signifies health in deciduous trees; hanging onto them is quite the reverse, indicating disease or death of the limb.

If freeze damage has produced more drastic effects, such as a plant that’s slumped into the ground looking mushy (summer bulbs, some sedum and occasional plants in pots), lift or trim out the squashed leaves and cover the crown with about 2 inches of mulch or leaf mold.

Do not despair if plants look dreadful now. Watch them as spring progresses for new signs of growth. Experienced gardeners often say that winter damage may clear up as late as May or June with new spring growth. Wind damage will certainly be easier to spot. Branches raggedly snapped off need to be trimmed evenly.

Cut back to another growing branch or to the branch collar if the damage is near the trunk.

Pruning is addictive, at least it is for me. Once I start, I have to remind myself to look carefully at each branch before whacking. Visualize the shrub without the branch, and never remove more than about a third of the live wood.

What’s not to be pruned? Stop pruning if you approach any plants that have budded up for spring (unless the buds are dead). Azaleas, rhododendrons, forsythia and lilacs will carry their spring show now in the form of buds at branch tips.

You can still tidy the plants, but the best idea is to do it close to, during, or just after bloom. If you prune forsythia just before buds show color, the flowers will open in a vase, giving you an early spring. The closer plants are to blooming, the more successful you’ll be in encouraging indoor flowers.

A good resource is “Cass Turnbull’s Guide to Pruning” (Sasquatch Books, 2004; $17.95).

Garden expert Mary Robson is a retired area horticulture agent for Washington State University/King County Cooperative Extension. Her e-mail is