A good rule of thumb is that if the plant blooms on new growth, it can be pruned in winter, before the new season's growth begins and after the final bloom of the year. Be careful with spring-blooming shrubs—those usually can't be pruned in winter without damaging the flower buds and ruining the blooming season.
Q: When is the best time to cut back in the fall? A: “When they start to look too ratty for you and before the fresh new growth begins,” says Sarah. For plants that are frost-sensitive, wait until after the plants have gone through several hard frosts to ensure they're dormant before cutting back.
It's important to cut back foliage in the fall to protect flowering plants from disease and give them a clean start for regrowth as winter starts to turn into spring. However, there are some plants you can keep around through the winter since they benefit wildlife and still offer visual interest for your home.
To prevent the disease from returning the following year, we suggest cutting the plants back in the fall and removing any debris – no matter the variety! It will give your plants a clean start next season. *Destroy any foliage with symptoms of powdery mildew and disinfect pruners before trimming other plants.
Also, do not cut back hardy perennials like garden mums (Chrysanthemum spp.), anise hyssop (Agastache foeniculum), red-hot poker (Kniphofia uvaria), and Montauk daisy (Nipponanthemum nipponicum). Leave the foliage. It's important to protect the root crowns over winter.
When to take cuttings. The best time to take softwood cuttings is from mid-spring to early summer. Hardwood cuttings are taken later in the year, from mid-autumn to mid-winter.
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.
Some plants can overwinter as houseplants. The most successful are: geraniums, Boston ferns, and tropical plants such as begonia, caladium, coleus, and hibiscus. For these plants, the general rule is to give them as much light and humidity as possible; keep away from heat ducts. Some will benefit from artificial light.
It's a common misconception that tree maintenance cannot be done during the winter months, or that tree care companies don't operate during this time of the year. The reality is that winter is a good time for pruning and tree removal services.
Cutting back perennials in the fall is not only a great way to keep flowerbeds looking neat and tidy through winter, but it also aids greatly in keeping plants vibrant and blooming the following year. Removing spent foliage and blooms helps a plant focus on recharging it's roots and resources.
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.
Cut-back: To “cut a plant back” means to take the whole plant down to just a few inches. If it's a shrub, it's usually cut down to ~12-18” depending on the shrub. Perennials and grasses are usually back to only a few inches above the ground. The cut-back method is best done in late winter.
September/October is the ideal time to take cuttings from your favourite strains of tender perennials to increase your stock for next spring or to make sure they live on if the parent plants do not survive the winter.
Hardwood cutting are taken in the dormant season (mid-autumn until late winter) after leaf fall, avoiding periods of severe frost. The ideal time is just after leaf fall or just before bud-burst in spring. Although this type of cutting may be slow to develop roots and shoots, it is usually successful.
Hardwood cuttings are best taken in October and November once the new summer growth has gone woody.
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.
Pruning Too Early
If you prune too early in the season, there's a good chance you'll snip the buds right off their branches, which means no flowers in the spring. Before you cut, do a little research, like with our pruning guide, or just wait to trim until the plant has finished blooming for the year.
Pruning to remove damaged, dead or diseased parts can be done at any time of the year. Most trees and shrubs, especially those that flower on current season's new growth should be pruned in late winter or early spring before the onset of new growth.
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.
But fertilizing in winter (or late fall depending on your climate) can actually offer nutrients to strengthen roots (that do often continue to grow in winter despite dormancy.) Fertilizing helps it to prepare for winter dormancy and gives it nutrients to store for better growth in spring.
ANSWER: You should not fertilize plants that would normally go dormant here during the winter. This includes all hardy trees, shrubs, ground covers, lawns and most perennials. Plants that are expected to grow during the winter, however, may be fertilized now.