17 Trees and Shrubs You Should Prune in January

January can be a tough month for gardeners. Once the bustle of the holidays is over, I’m always left with a longing to get back outdoors in search of a serotonin boost. Things are looking a little bare out there, but that means it’s a great time to prune certain shrubs and trees. 

The ideal time to prune many deciduous trees and shrubs is while they are dormant. There are several reasons for this. First, it’s easier to see the interior of the tree and its general structure. You can make your cuts more deliberately and get a better view of the shape you want to create. 

What Types of Plants to Prune in Winter

Deciduous trees and shrubs that bloom or bear fruit on new growth are the ones to prune in winter. This includes most fruit trees and nearly all deciduous trees that are not fruit-bearing. The exceptions are shrubs and trees that set buds on old wood, as these are already formed. 

Avoid pruning trees like magnolias, forsythia, lilacs, oakleaf hydrangeas, cherry trees, rhododendrons, and lavender. If you’re unsure about a certain plant, look to see if they set buds on the previous year’s growth. These are the ones to steer clear of in winter. 

If you prune these, you risk cutting off buds and reducing or eliminating blooms for the upcoming year. Do any trimming of these immediately after they drop their blooms to allow the greatest amount of time to form new, strong buds. 

Reduce the leader, or top branch, by about one-third to reduce the height and make it easier to harvest. Remove a quarter to a third of the overall growth from the previous year to conserve energy, directing it to new growth, lower to the ground. This makes your job easier in years to come. 

Apples should grow in a pyramidal shape, with the leader about two to three feet taller than the next set of lateral branches. Make sure to trim any waterspouts (branches that grow straight up) and crossing branches. Branches that cross through the center decrease airflow and sun to the center, as well as potentially weaken those they rub against.

Pear

	botanical name Pyrus communis
	sun requirements Full sun
	height 8’-50’
	hardiness zones 4-9

Pears are much like apples in their needs. They prefer a pyramidal shape with a central leader. This shape allows for the best light and air circulation to the interior. Aim for evenly spaced branches with a bottom-heavy distribution for easy harvesting. 

Remove any damaged wood first and survey the shape of the tree.  Identify branches growing downward, upward, and inward. These are all those that generally interrupt the shape, which should be conical with lateral branching. Then, cut back the previous year’s growth by one quarter to one-third. 

Maple

	botanical name Acer spp.
	sun requirements Full sun to partial shade
	height Up to 150’+
	hardiness zones 3-9

Prune your maples in winter while they are dormant. These will bloom on new growth, and trimming them now helps them heal faster and get a more vigorous start in the spring. You won’t need to prune in the first few years unless you are going for a specific shape. For young trees, a light trimming can stimulate dormant buds, which is good for branching. 

Remove all dead and damaged wood first and survey the interior. If cutting entire branches, cut parallel to the trunk, leaving the collar intact. Remove water spouts and crossing branches to thin out the interior. Never remove more than one-quarter of the tree’s total branches in a single session. 

Elm

	botanical name Ulmus americana
	sun requirements Full sun to partial shade
	height Up to 100’+
	hardiness zones 3-9

Winter is the time to trim your elms, as the cold weather prevents them from excessive sap leakage. They don’t produce sap while dormant, which prevents diseases transmitted by sap-feeding beetles. It reduces stress and is easier to see the overall shape during this time, as with most deciduous trees. 

When removing branches at the trunk, always leave the cob llar. Don’t cut them off flush. For larger oaks, it can be helpful to employ an arborist, as they will know how to best care for this tree. Never cut your oak back by more than one-third in a single session. They don’t take well to hard pruning. 

Ash

	botanical name Fraxinus
	sun requirements Full sun to partial shade
	height Up to 80’
	hardiness zones 2-9

Ash trees are tall and have a dome-shaped canopy, making them great shade providers. They are moderate growers and can grow quite tall over time. Begin when your ash is two to three years old, and correct the form while branches are small. Remove weak ones and trim back to just beyond a bud to encourage branching. 

As ashes can grow very large canopies, it is sometimes best to pollard them. This involves removing the upper branches to encourage a shorter trunk and sturdier lower half. This reduces the risk of falling limbs that can cause damage. It’s best to employ an arborist for this process to avoid harming your ash.

Arborists will also be able to check and treat a potential emerald ash borer infestation before they do damage to your tree.

Beech

	botanical name Fagus sylvatica
	sun requirements Full sun to partial shade
	height Up to 60’
	hardiness zones 4-7

Beech trees produce sap, and this decreases during dormancy. Pruning in winter reduces their vulnerability to sap-feeding pests. You can begin as soon as they lose all of their leaves, but waiting for colder weather is a good safeguard. Beeches are dense, upright growers with an oval-shaped canopy. 

Leave large beeches to an arborist. They can grow very tall and wide over time. Prioritize removing dead, diseased, or damaged wood. Thin out the canopy by removing crossing branches or those that grow straight upwards. Removing lower limbs while it is young will contribute to an attractive shape as it ages. 

Ironwood

	botanical name Ostrya virginiana
	sun requirements Full sun to full shade
	height 20’-40’
	hardiness zones 3-9

Ironwoods produce sap, so they are among those that you shouldn’t cut while they are in active growth. Pruning in summer can interrupt the natural shape, as well. While it is young, remove the bottom one or two limbs yearly to achieve the desired clearance. Large, mature ironwoods are best left to professionals. 

In the interim, before it is too large to manage, prune in late winter. Remove damaged wood and thin out the interior to improve airflow, which prevents diseases. Make sure to use clean, sharp cutting tools on this one, as it is vulnerable to diseases. 

Walnut

	botanical name Juglans spp.
	sun requirements Full sun
	height Up to 150’+
	hardiness zones 4-9

As with others on the list, walnuts benefit from pruning in late winter to early spring while they are dormant. This reduces the amount of ‘bleeding’ they do and helps them to heal faster and grow more robustly in the spring. As they mature, trim your walnuts every three to five years. 

Try to make precise cuts to avoid that bleeding we talked about. These grow quite tall, so you can cut the leader to restrict the overall height. Remove all damaged or diseased limbs and those that cross each other or the center. Avoid horizontal cuts where water can pool. 

Hawthorne

	botanical name Crataegus monogyna
	sun requirements Full sun to partial shade
	height 10’-30’
	hardiness zones 5-7

Hawthorns are bleeders, so to avoid a strong sap flow, winter trimming is best. It also encourages a strong bloom in the spring. Unlike most trees, prune these regularly when they are young to create an attractive shape and structure. As they age, every three to five years is adequate. 

For your hawthorne, cut close to the branch collar but not flush with the trunk. Make cuts just above a bud, and plan these cuts so that the bud faces the direction you want the branch to form. You can also remove lower limbs to create more clearance and create a treelike shape. 

Dogwood

	botanical name Cornus florida and C. kousa
	sun requirements Full sun to partial shade
	height 15-30′
	hardiness zones 5-9

Pruning your dogwood shrub or tree in winter helps to protect it from pests and diseases. These tend to be vulnerable to a number of issues, so this is an added protection that you definitely should keep in mind. It also helps to maintain an attractive shape, as it will control growth. 

For shrubby dogwoods, trim them close to the ground for the first several years. This will encourage lateral branching. If you want a more tree-like shape, trim the lower limbs until you reach the clearance you desire. Remove dead and diseased wood, and trim out twiggy growth. If you desire, you can thin out the crown to give added disease resistance. 

Sumac

	botanical name Rhus glabra
	sun requirements Full sun to partial shade
	height 3’-20’
	hardiness zones 3-9

Except for African sumac, these large shrubs are best pruned in winter. Trim them before new leaves emerge. January is ideal in most climates. Make any cuts where the stem attaches to a branch or trunk. Pruning should help to balance out growth.

It’s important to keep branches off the ground, as they will root where they lie, and the plant will spread and create a thicket. Remove all damaged wood first, and don’t hard prune this one. Don’t cut back by more than one-third in any single year.

Hazel

	botanical name Corylus spp.
	sun requirements Full sun
	height Up to 50’
	hardiness zones 4-9

Hazels, which include hazelnuts, are best pruned in the winter. It promotes healthy new growth, and helps it to heal faster. You can also prune after blooming, but they heal faster if you do your cutting in winter.

Always make your cuts at the branch collar. Remove crowded branches, twiggy growth, and any dead or diseased growth. Remove suckers as well. These are water spots that grow from the base of the plant. These do not take well to hard pruning, so never cut back by more than one-third of the total size. 

Willow

	botanical name Salix spp.
	sun requirements Full sun to partial shade
	height 3’-65’
	hardiness zones 2-9

All willow pruning should happen while these plants are dormant. This helps you to see the overall shape, which is particularly important in shaping a weeping cultivar. It reduces stress, as well, and minimizes the spread of diseases. Doing so will give you plenty of healthy growth in the spring. 

Clean your tools well to protect this rather vulnerable tree from diseases. Don’t remove more than one-quarter of the plant in one year to avoid causing undue stress. Remove any suckers and water-spouts, and trim for a generally pleasing shape. 

Panicle Hydrangea

	botanical name Hydrangea paniculata
	sun requirements Full sun to partial shade
	height 8’-25’
	hardiness zones 3-8

Hydrangeas are not all the same when it comes to pruning. Only prune oakleaf hydrangeas and bigleaf types right after they bloom, as they set buds on old wood and will not bloom if you cut off the buds in winter. Panicle hydrangeas bloom on new wood, however, so pruning them in winter promotes vigorous growth and thus, increased flowering. 

When you prune your panicle hydrangea, remove crossing branches to keep the interior open and give an overall pleasing shape. Always make cuts just above an outward-facing bud to encourage a rounded form. Cut these back by about one-third to keep them branching and maintain a nice shape. 

Crape Myrtle

	botanical name Lagerstroemia indica
	sun requirements Full sun
	height Up to 30’
	hardiness zones 6-9

Crape myrtles are one of my favorite trees to prune. They are also the ones I wince most over when I see the choices some of my neighbors make. Winter is the right time to prune these, as well, and for much the same reason as others. It promotes healthy growth, branching, and thus, more flowering. 

As far as how to cut these, there is a fad to simply lop the top of the tree off just above the trunk. We call this crape murder because it ultimately shortens the life of the crape myrtle, increases the likelihood of pests and diseases, and disfigures it permanently. It might look nice for a few years, and it does create a fun shape, dense foliage, and a ton of flowers, but it’s not good for longevity or health. 

Instead of lopping off the top, trim your crape myrtle into an open vase or chalice shape. The branches should gracefully grow upward and arch out at the tops. Trim away crossing branches in the interior, and if you want to increase the bloom, you can lightly tip the ends of the branches. 

Spiraea

	botanical name Spiraea prunifolia
	sun requirements Full sun to partial shade
	height 1’-8’
	hardiness zones 5-8

Spireas are beautiful blooming shrubs, and they are best pruned in the winter while dormant. This will help to rejuvenate the plant and encourage bushier growth in the spring. These can tolerate hard pruning, and it will actually stimulate bushier, more floriferous growth.