Prune most broadleaf evergreens now: abelia, boxwood, cleyera, elaeagnus, nandina, privet, and holly. Wait until after flowering for spring bloomers. Viburnums (both evergreen and deciduous) can be cut back hard to reduce size, but you will sacrifice flowers for the season. Wait until after flowering for light pruning.
In fact, it is better to prune a little at a time than to make drastic cuts. For plants that shed their leaves (deciduous plants), the best time for winter pruning is from the beginning of November to the end of February. To prune evergreens you can start later, from mid-December, and continue until February.
For most trees, the best time for major pruning is late winter to early spring because wounds close faster. Pruning in late summer and early fall may also stimulate new growth, which has little time to harden before cold weather comes.
Don't shear the branches of spring flowering shrubs (Forsythia, Lilac, New Mexico Privet, Spirea, Flowering Quince, and others). These shrubs produce flowers on last year's wood, so removing old growth will reduce or prevent flowering. These plants should be pruned immediately after they are done blooming.
Plants are more brittle in cold temperatures. Messing around with them may cause branches to snap and split unintentionally. It's minor, but it could impact the look of a plant or create a haven for insects and diseases later. Don't prune when the temperature falls below 25°F.
Winter is usually the best time.
Without the leaves, you can easily see the branching structure of the shrub and decide what to cut. Dormant pruning is usually done in late winter, six to 10 weeks before the average last frost in your area.
Late winter is a good time to prune most plants. Because plants and their pests are dormant this time of year, pruning cuts can be made without the risk of pests and pathogens entering the tree through the wound.
Watering is very important during the couple of weeks or more that a plant is recovering from root pruning. Right after pruning, I give the whole pot a thorough soaking. As new growth begins, I make sure to thoroughly wet all the soil at each watering.
The 1/3 rule involves cutting about 1/3 of wood during any pruning activity. This moderate pruning practice is a balanced approach to thinning out shrubs to stimulate new growth. The plant loses a good amount of stems, usually on the top section, allowing more light and air to enter the inside of the plant.
Van Volkenburgh says plants can also respond defensively to physical disturbances like being cut open or wounded. But that doesn't mean they perceive painful stimuli the same way a human or animal would, with all the emotional connotations that come with it.
Some perennials, like hostas, peonies and daylilies, need to be pruned in fall to avoid winter damage. Plants like these should be pruned after the first few frosts in late fall or early winter. Other perennials like mums and coneflowers are better off being pruned in spring just before new growth comes in.
Japanese yew (Taxus cuspidata) is a good choice for an outdoor winter plant because it's an evergreen that keeps its leaves on its branches all winter long. It's drought-tolerant and thrives in both full and partial sun. Hardy to Zone 4, Japanese yews can survive harsh winters.
After “how?", the second most-asked question we get about pruning is “when?” (Or, "Can I prune this now?") The rule of thumb is to prune immediately after bloom for flowering shrubs, in late winter or early spring for non-blooming shrubs (particularly for heavy pruning), and not after mid-August for any shrubs.
DON'T prune during fall.
No matter what type of shrub you have, fall pruning can stimulate late-season growth that may not have enough time to harden. This can weaken and damage the plant—especially if there's an early frost. Instead, wait until winter and trim bushes when the plant is in deep dormancy.
Deep water plants before ground freeze, and continue to water during winter months when temperatures remain above freezing but without precipitation, Erect physical windbreaks. Wrap problem plants with burlap or other material to protect from wind and subsequent moisture loss to evergreen shrubs and small trees.
You should trim your hedges at the same time of year you trim most of your trees — late winter to early spring. If your hedge has gotten out of hand, power hedge shears may be the best way to begin. Follow up by hand with freshly sharpened hedge trimming shears to clip away all the stray leaves or branches.
As mentioned earlier, watering plants several hours before a freeze is the first defense against damage. During a temporary cold snap, cover entire shrubs with burlap, sheets or blankets for insulation. For the best protection, use a frame to prevent the covering from touching the plants.
But late winter is an ideal time to prune most roses, while the plants are dormant and unlikely to put out tender, new growth that would be damaged in freezing weather. It's usually safe to prune roses in January or February, but perfect timing really depends on the type of roses you're growing and your hardiness zone.
An improper cut like a flush cut (cutting too close to the trunk) or a stub cut (cutting too far from the trunk) can cause irreversible damage to a tree. A flush cut removes the branch collar and leaves a large wound in the side of the tree that won't heal properly.
Overgrown trees can pose a serious risk to your property and your family. Dead or damaged branches can fall and cause damage to your home or car or even injure someone. In addition, overgrown trees can block sunlight and views and can even damage foundations or driveways.