Dormant Season Pruning Tips
By Bob Chapman
Winters breath slowly covers the land and many deciduous shrubs and trees are entering into their winter's sleep. Their leaves have fallen and we can easily see the branches and twigs. In our mild winter climate we can shear or prune evergreens in winter with no harmful effects. This article concentrates on the deciduous shrubs and small trees in the landscape.
Reasons for pruning in the dormant season
- The bareness of deciduous shrubs and trees shows us the crossing branches and the errant, wayward shoots just begging to be clipped.
- Dead and diseased twigs and limbs need removing to keep the rest of the plant healthy.
- Sometimes we need to limit the height and width of deciduous shrubs and small trees.
- Fruit trees must be correctly pruned to get the maximum fruit production next summer.
- Many deciduous shrubs need pruning to boost flower production as their flowers are produced mainly on the new wood sent out next spring.
- We prune or trim bonsai, hedges, topiaries or overgrown evergreen shrubs to maintain shape or heights. Winter, when most plants are dormant, is an ideal time to do this.
Suggestions for pruning common dormant fruit trees
- Apples. These trees produce a crop on thick, stubby fruiting spurs that will produce a crop for about twenty years. Remove suckers and water sprouts and any crossing branches. You want to keep the center open so thin out enough new growth to achieve this goal. Pruning apple trees goes quickly and easily, just don't harm the fruiting spurs.
- Apricots. These fast-growing, vigorous trees need heavy pruning for good fruit production. Most fruit is found on short spurs that form one year and bear fruit the next. These spurs will bear fruit for about three years. Each year remove old, worn out unproductive branches, cutting back to younger, vigorous branches bearing fruiting spurs or to new branches that will produce fruiting spurs this year.
- Cherries. The fruit on these trees are produced on long-living spurs and you won't need to prune for fruit production. Remove weak growth and any branches that crowd the center, keeping the center of these upright trees open.
- Fig. Fig trees are very accommodating as they will produce a crop with no dormant season pruning, but will produce more if you prune out the weak and unnecessary growth in the canopy, keeping the center open to let in light. You can cut back branches to keep the tree in bounds or limit the height or spread.
- Peaches and nectarines. These fast-growing fruit trees need heavy pruning to produce those luscious fruits. They will produce crops if not pruned but on branches that are further away from the center. The weight of the fruit will break branches. Each year's new growth produces fruit the following season. Either remove two-thirds of the wood of the fruiting branches or remove two-thirds of the branches to keep the tree in suitable size and productive. Yes, I said TWO-THIRDS! Most home gardeners are reluctant to take off that much growth. But if you cut off two-thirds of each branch you will have wonderful crops of delicious fruit next summer.
- Pears. Annual pruning of established, mature trees consists of removing any weak, diseased, dead or broken branches and any branches or shoots that crowd the center, not letting light to it. To control the height cut back the upper branches to an outward-pointing side branch. Refrain from cutting back the lower branches.
- Persimmon. The wood of the persimmon tree is brittle and a heavy crop can break branches. Remove dead wood and watersprouts. Thin out crowded twigs and branches in the crown.
- Plums and prunes. These trees produce fruit on spurs that during the dormant season the spurs appear as clusters of buds flush with the stems. Many plums produce several upright stems that need thinning out each year, keeping the center of the tree open and leaving branches that can bear the weight of the fruit. European plums need relatively little pruning whereas Japanese plums are very vigorous in their growth, producing many long shoots each year and need more pruning.
Suggestions for pruning common flowering deciduous shrubs
- Buddleia davidii, the "Butterfly Bush." This shrub grows prodigiously each summer, producing vast amounts of growth and masses of flowers that butterflies flock to. You have to be somewhat brutal in pruning this popular shrub. Cut out the weakest stems and then cut the remaining strong stems back by two-thirds. Yes, 2/3! Next summer you will again have those masses of flowers.
- Hydrangea macrophylla, the more common garden type. Many gardeners prune their hydrangeas by removing the spent blooms in the summer. These flowers are produced on stems from the previous year. After the flowers are cut back, new growth will begin lower on the stems. Cut the flower stems back to the strongest pair of new shoots or to a pair of buds that will send out stems where you want them. Make the cuts leaving two pairs of buds that grow from the ground or two pairs of buds on the side branches. Thus, you will be directing the growth and shape of your hydrangea, possibly filling in some blank spots. When your hydrangea has lost its leaves, remove dead, crossing, broken or crowded branches. If you had not pruned back your hydrangea in summer as described above then follow the guidelines above. The challenge is determining the stems that bore flowers last season.
- Punica granatum (Flowering Pomegranate). The beautiful flowers that this shrub or small tree produces are breathtaking. To keep the flowering pomegranate producing blooms simply thin out very old and weak stems and any crowding branches. If grown as a small tree, remove any side branches on the trunk and any suckers arising from the base.
- Rose of Sharon (Hibiscus syriacus). Thin out any crowded stems and remove any that are dead, broken, diseased and older non-productive stems. To keep this aggressive grower in bounds, cut back the stems to lateral branches or growth buds.
- Spiraea There are two distinct species of Spiraea, the familiar "Bridal Wreath" type (Spiraea prunifolia) that blooms in early spring with white flowers cascading down arching branches or the shrubby type (Spiraea japonica, with its very many named varieties) with clusters of pink flowers in summer. Prune the "Bridal Wreath" Spiraea after it blooms. Do not cut back those with arching stems; you'll ruin the graceful form. Instead cut off a few of the older stems to the ground each year. These will be replaced with new ones that will bear new flowers two summers away. Prune Spiraea japonica now. Summer-blooming Spiraea japonica needs heavy pruning. Thin out older stems and head back (cut off) the younger ones to as few as two buds. This will give you larger flower clusters next summer on a smaller plant.
Deciduous shrubs and small trees that are pruned AFTER they flower.
It is tempting to take loppers and pruning shears to all dormant deciduous plants, but these shrubs and small trees are pruned after the flowers are gone.
- Cornus florida (flowering dogwood)
- Flowering Quince
- Flowering Peach
- Forsythia
- Jasmine
- Kerria japonica
- Lilacs
- Mock orange
- Ribes (Gooseberries)
- Spiraea japonica
- Weigela
Deciduous common small trees
Usually these small trees can be easily pruned with a pole pruner or long-handled lopping shears.
- Crataegus (Washington Hawthorn). These small trees are naturally twiggy and dense in their growth habits. They need little pruning. Prune only to open up the tree to allow wind to go through. Cut off any dead or diseased twigs and branches. Remove all growth that appears along the trunk.
- Flowering plum. Cut out any crossing and inward-growing branches and extra-vigorous vertical branches. As these trees branch densely, thin their centers frequently. Avoid cutting back branches to limit the size of flowering plums as this will cause profuse sprouting.
- Lagerstroemia indica (Crape Myrtle). Remove all dead and broken branches and any twiggy or crossing stems. Cut back any too-long branch to a lateral. Cut back last year's new growth by 12-18 inches to promote flowering.
- Malus (Flowering crabapple). It is better to prune these trees after blooming but it does stimulate less new growth on the tree. In the dormant season prune out weak, thin, crowding branches and any that cross over the center.
- Weeping flowering cherry. Prune off any too-vigorous shoots to keep the tree in balance and promote branching. Prune out any diseased, weak or dead branches or twigs. If desired, remove lower limbs to afford room to walk under the tree.
Mature Shade trees.
Pruning these is best left for the professionals. Most home gardeners do not possess the tools needed nor have the skills to tackle the job.