You may dream of spending winter inside under a down comforter, but winter is an excellent time to catch up on your tree care. In fact, many tasks are better done during dormancy than during the summer growing season. Read on for winter tree care tips to keep your trees healthy, thriving, and ready for spring.
Winter Tree Care Benefits
Winter is an excellent time to evaluate your trees. Winter weather means dormancy and bare branches, which make inspecting crown structure much easier. You can identify diseased, damaged or crossing branches, easily spot hazards, and prune to balance and refine a tree’s branch structure. If indicated, late winter spraying for overwintering pests or pathogens is easier without an intercepting crown of leaves.
The frozen winter ground is also an asset, as it reduces the chance of damage from large machinery. Heavy vehicles and their large wheels can gouge soils and cause compaction during warm weather when the soil is soft and friable. In winter, the frozen ground is firm and can better support the weight of maintenance vehicles.
Tree Care Tasks to do in Winter & Why to do Them
Remove Large Trees
Consider making use of winter weather to remove any hazardous or diseased trees.
Why do this?
- You won’t disturb bird nests, fruit production, or pollinators, which are some of the important summertime assets and beneficiaries of trees.
- Access to and removal of trees will be easier on the solid ground (as long as there isn’t too much snow!).
Prune Dormant Trees & Shrubs
There are some vital reasons for pruning your trees when winter dormancy is in effect but the promise of spring is on the horizon. For complete details, see our article about winter tree pruning.
Why do this?
- It’s easier to see what needs to be done when the branches are bare
- You can prevent damage from snow and ice loads if you remove weak, damaged or poorly-supported branches
- Pathogens that spread diseases, such as Dutch elm disease, oak wilt, blight, and rust, are dead or dormant during winter. As a result, the wounds from pruning cuts are far less susceptible to attack from these diseases.
- When pruning is done in late winter, pruning cuts are quickly compartmentalized with the first flush of spring growth.
- You’ll have more visually appealing winter views with trees and shrubs whose bare branch structures have been shaped and refined.
Wrap Tender or Vulnerable Shrubs & Trees
Broadleaf evergreen shrubs, as well as plants exposed to winter road salt or de-icing products, can be protected by wrapping them with burlap. It’s best (and easiest!) to get the wraps in place before snow starts to fly. And don’t forget to unwrap tender plants as soon as temperatures rise!
Why do this?
- Road salt is easily sprayed on nearby plants by passing vehicles, damaging (and sometimes, even killing) unprotected plants.
- Broadleaf evergreens are susceptible to winter die-back when exposed to cold, dry weather, especially when planted in sunny or windy locations.
- Wrapping also prevents deer browsing, and we all know how hungry deer can quickly reduce a shrub or tasty arborvitae to nothing but stubs!
Spread Mulch to Protect Roots
Compost and mulch, applied before winter freezing, will help trees get through winter. Spread a 2 to 4-inch layer of mulch over the root zone of trees and shrubs, being careful to keep it well away from the trunk. Check out these details about how to properly apply mulch before you get started. If you have a lot of fallen leaves each autumn, you can also use those to create a nice winter cover of mulch.
Why do this?
- Nutrients from the compost and decomposing mulch will be available immediately upon spring bud break and the start of the growing season.
- Soil warms up faster in spring, and stays warmer in winter, under a blanket of mulch.
Keep Watering Newly-Planted Trees
Any trees or shrubs planted within the past two years should be checked over the winter to ensure the rootball isn’t drying out, particularly if we’ve had very dry weather in fall. Depending on their condition, you may want to continue watering these plants in winter.
Wait for clear days when temperatures are above 40F and there’s no snow cover. Apply water at mid-day to give it time to soak in before the ground freezes at night. Give your plants a long, slow trickle of water to keep the soil moist but not sodden – if you have clay or poorly-draining soil, skip the winter watering. For complete details, see our article on how and when to water trees.
Why do this?
- Even though trees are dormant in winter, they still need sufficient moisture to support their essential “life support” functions.
- Warm, windy fall weather can quickly dry out the soil before winter arrives, and the cold, dry air of winter makes the situation worse.
- Lack of soil moisture can result in death to plant roots before the winter is over.
Check for Rodent Damage to Tree Trunks & Roots
When snow blankets the ground, it’s difficult to see whether rodents (such as voles and gophers) are snacking on the base or roots of your trees. Clear snow away from young trees and shrubs to create an open area that leaves rodents visible to predators (these pests prefer to remain hidden so may not risk exposure to try to reach your tree). You can also wrap tree trunks with wire mesh to prevent rodents from reaching the bark.
Why do this?
- Winter rodent damage can be severe (if they eat the bark around the entire circumference of the trunk, it can kill the tree) so it’s best to prevent it, rather than trying to treat damage after the fact.
- Most damage isn’t noticeable until snow melts in spring – and by then it’s too late. Checking your trees and keeping the area clear of snow makes any damage immediately obvious.
It can be very satisfying to watch your trees and shrubs go from winter dormancy to spring budding and bloom. Learning to anticipate and respond to the seasonal requirements of your plants is the best way to ensure their continued vigor so you can enjoy many more years of spring blossoms, summer shade, and colorful fall foliage!