When to Prune Shrubs and Hedges in Northeast Ohio, and What to Leave Alone Until the Right Season

Once the leaves are down, overgrown shrubs and hedges are easy to see, and November is when a lot of people pick up the pruners. Iowa State and Penn State both advise against fall pruning for most shrubs. Pruning the wrong shrub in the wrong season can remove next year's flowers, or push out new growth that winter cold may damage.

This post sorts shrubs by when they should be cut, using Iowa State University Extension, Penn State Extension, and Ohio State University Extension sources. One caution up front: Iowa State's dates are written for Iowa, so treat them as a guide to the order of the jobs rather than a Tuscarawas County calendar.

The Short Version for November

For most shrubs and hedges, fall is not the time. Iowa State says to avoid pruning evergreen shrubs in the fall, because fall-pruned evergreens are more susceptible to winter injury, and not to prune deciduous shrubs in late summer, since pruning in August or early September can trigger late growth that winter cold may damage. Penn State Extension's page on flowering shrubs calls late summer and fall pruning not desirable for the same reason: new growth at that point is vulnerable to winter injury.

The exception is wood that is dead or hazardous. The University of Delaware's fact sheet on pruning evergreens says dead, diseased, and broken wood on evergreens can be removed any time of year, and Ohio State's fact sheet on pruning and tree wounds says hazardous tree limbs should be removed regardless of the time of year.

Bloom Time Decides Everything for Deciduous Shrubs

The rule that matters most is when the shrub flowers, because that tells you when it sets its flower buds. Penn State explains that spring bloomers form their buds on old wood, which is wood that grew the year before, so pruning them before they bloom removes the flowers. Iowa State says the best time to prune healthy, well-maintained spring-flowering shrubs such as lilac and forsythia is immediately after flowering. Penn State draws the line at mid-June: shrubs that bloom before then should be pruned after they flower. John Kaskewsky, an Erie County master gardener writing on Ohio State Extension's Erie County site, says azaleas, lilacs, and forsythias should be pruned a couple of weeks after the blooms have faded.

Summer bloomers flower on the current season's growth, so they can be cut before growth starts. Iowa State lists potentilla and Japanese spirea and says to prune summer-flowering shrubs in late winter or early spring. Penn State gives the same timing, and Kaskewsky puts butterfly bush and panicle hydrangea in the late winter group.

A badly overgrown shrub is the case that costs you something. Iowa State says rejuvenation pruning is best in late winter or early spring, but that heavy pruning will reduce or eliminate the flower display on spring-flowering shrubs for two or three years. Penn State's advice for an overgrown shrub that no longer flowers is to cut all stems to the ground in early spring, and it warns that this may delay flowering for several years.

Hydrangeas Are the Classic Trap

Hydrangeas are the shrub most likely to be pruned at the wrong time, because the common types follow opposite rules. An Ohio State Extension Fairfield County article says the answer begins with knowing which species you have. Smooth and panicle hydrangeas, which bloom on new wood, can be pruned in late winter or early spring before new growth emerges. Bigleaf, oakleaf, mountain, and climbing hydrangeas flower on old wood, and the article says they should not be pruned in late winter or early spring.

The article says the answer begins with knowing which species you have, so identify the plant before cutting. It points to Ohio State fact sheet HYG-1263, Selecting Hydrangeas for the Home Landscape, for more on telling them apart.

Evergreens: Early Spring, and Not in the Fall

Iowa State says to prune evergreen shrubs such as juniper and yew in late March or early April before new growth begins, with light pruning also acceptable in mid-summer. Those are Iowa dates, so in Tuscarawas County read the rule as early spring, before new growth starts. The University of Delaware fact sheet, written by Jay Windsor and revised by Susan Barton, likewise says early spring is best for juniper, arborvitae, yew, and hemlock, with additional light pruning later in the season if needed.

How hard you can cut back is where evergreens differ from deciduous shrubs. The Delaware fact sheet cautions that care should be taken not to cut too far back into the older wood, and says new growth is not as readily produced from old wood. It also says yews can take exceptionally severe pruning into the older wood, so the plant matters. Boxwood gets its own timing from Iowa State: remove dead growth in early to mid April (Iowa dates again), do light shaping from spring to mid-summer, and do not prune in late summer, because late growth may not harden off before winter.

Hedges: Timing and Shape

Two Iowa State pages give slightly different starting dates for evergreen hedges. The page on formal hedges says early spring, usually April, is the proper time to begin pruning them. The page on the proper time to prune trees and shrubs says to begin shearing in late spring or early summer after new growth appears, which it puts at May through early June, and to avoid extensive pruning after mid-summer. The two pages differ by about a month on when to start, and only the second gives the mid-summer cutoff.

For deciduous hedges, the formal hedge page says extensive pruning is best done late in the dormant season, which it gives as late February and March in Iowa, with spring-flowering hedges such as lilac pruned immediately after blooming instead. The proper-time page adds that most deciduous shrubs should not be sheared into formal hedges at all, with privet, alpine currant, and barberry as the exceptions.

Shape matters too. The formal hedge page says a hedge should be narrower at the top than at the bottom, so lower branches get sunlight and stay dense, and so less snow builds up on top where it can break branches.

What You Can Do This Month

Not much, and that is the point. Dead and hazardous wood is the exception described above. Kaskewsky recommends starting with dead, diseased, or damaged wood, cutting just above a bud or at the branch collar without leaving stubs, using sharp tools, and disinfecting them between cuts. He also says not to remove more than about one-third of a tree's canopy or a shrub's structure in one season.

Where the Sources Differ About Winter

Late winter is the usual advice for summer bloomers and deciduous hedges, but not every source treats winter pruning the same way. Kaskewsky calls late winter the perfect time to get into the landscape, because most plants are dormant and pests and diseases are dormant too, and he lists maple, oak, elm, crabapple, dogwood, and others among the trees and shrubs to prune then.

Ohio State's fact sheet HYG-3311-09, by Nathan Kleczewski, Pierluigi Bonello, and Jim Chatfield, is about trees and does not address shrubs or hedges. It says the best time to prune many trees is when growth and callus formation are greatest, and that in Ohio this means spring to early summer, March to June. It also warns of problems for some tree species with any pruning in the winter months, because of an increased chance of winter freeze injury. That does not overturn the shrub guidance above, but it is a reason to look up a specific plant before cutting it.

When to Call Stoll's

Stoll's Landscaping trims shrubs and hedges in Dover, New Philadelphia, Sugarcreek, Strasburg, Bolivar, and Uhrichsville. We look at the plants first and tell you how much to take off, and we clean up the clippings when the work is done.

Send photos of the shrubs or hedges, your address, and rough lengths if you have them, and we confirm scope, timing, and pricing before any work begins. Large tree work falls outside our typical scope.