Winter Tree Care & Planting

Before the rush of spring gardening, with all the excitement of visiting nurseries to find new shrubs, perennials and seasonal color, think about one of the most valuable parts of your landscape: trees. While winter may be a dormant time for trees, it is an excellent time to care for trees in your landscape and consider planting a few new ones.

Tree Planting

Planting a quality tree will pay off dividends in time. The tree will grow every year creating more shade to enjoy on hot summer days while also helping decrease your energy bill. Trees provide a natural wildlife habitat, attracting birds to your garden all year. And there is the added benefit of increased property values. If you have the space, then a good tree is a win-win proposition! (See Why I Love Trees and You Should Too!)

Winter Planting

Planting in the winter has several advantages: while trees are dormant, they will suffer less stress and quickly adapt to their new location. Winter planting also allows trees time to grow new roots before the heat of the summer. Trees grow roots all winter, and putting on new growth is much easier with cooler temperatures and winter rainfall.

Just keep in mind that winter weather in North Texas has become unpredictable in recent years due to climate change. Prolonged freezes, combined with dry conditions, can damage all trees, whether newly planted or well-established. Take steps to protect your trees if extreme conditions are expected. 

If you don’t want to risk winter planting, then now is the prefect time to research and plan for new trees to get a headstart on spring planting season. You’ll typically find better availability of plants at nurseries come springtime.

What to Plant

Before you plant, make sure you are choosing the right tree for your landscape. Find out the mature size of the tree to make sure it will have plenty of space to grow. Factor in enough room for the tree to fully mature without crowding other trees or your house.

Oaks, for instance, are very large trees at maturity (full size), anywhere from 40 to 60 feet tall and wide. Plant at least 20 feet from your foundation. If planting off a corner of your house, you can plant 15 feet away.

A high-quality shade tree is your best defense against ice and freeze damage. Bradford Pears, for instance, may be widely available, but they are weak and short-lived. Consider instead a high-quality, long-lived oak. My personal favorite is a Bur Oak that is over 100 years old. The structure of the trunk and branching is a thing of beauty, especially in the winter.

For help choosing the right tree for your space, check out this Texas Tree Planting Guide which includes options to select native and drought tolerant trees.

Tree Buying

Once you know what tree you want, it’s time to pick a specimen from the nursery. First, I recommend you visit a local nursery (not big box store), ideally one that grows their own trees from locally sourced seeds.

Buying an oak tree or any other deciduous tree in winter when they have lost their leaves will allow you to see the main trunk and branching.

What to look for when selecting a tree at the nursery:

• A straight, single leader (a main, upright trunk)
• Secondary branching should be at a 45 to 90 degree angle for strength
• No damaged bark or broken limbs
• A moist root ball with no exposed or circling roots

To check if a dormant tree is alive, snap a small twig or scratch the bark to look for a green interior.

How to Plant

When you have the right tree for the right place, follow these basic planting guidelines to give your new tree the best start.

1. As with planting any newly purchased plant from a nursery, soak in a bucket of water for at least 20 minutes. If you don’t have a bucket big enough, let a small trickle of water from your garden hose soak the root ball for half an hour.
2. Dig a hole 2-3 times the diameter of the root ball.
3. Gently cut any roots that are circling around the container.
4. Ensure the root ball is on firm soil in the hole you dug (the top of the root ball should be level with the ground), then back-fill with the soil you dug out.
5. When you have filled the hole halfway, water thoroughly and let it soak in before adding the rest of the soil. Water again to remove any air pockets in the planting hole.
6. Add 2 to 3 inches of mulch to the planting area to insulate the soil, suppress weeds, retain moisture, prevent soil compaction, and add nutrients. Be sure to keep the mulch away from the tree trunk to prevent exposure to pests and diseases.

Winter Tree Maintenance

Just because your trees are dormant at this time of year doesn’t mean you can neglect them! Some basic maintenance now will ensure your trees remain strong and healthy year-round.

Watering & Protecting from Winter Weather

Watering your trees in the winter during the first two years after planting will help get them established.

How much to water and how often depends on climate, soil, wind, and sun conditions. Trees in full sun and subjected to windy conditions will require more watering. If your soil is sandy loam or just sand, it will need more water. Before watering trees in clay soils, check the moisture level with a moisture meter. Clay soil tends to stay wet in the winter.

Roots can be damaged by freezing temperatures if the ground is dry, the north wind is blowing, and it hasn’t rained for weeks. Before a hard freeze, check the soil around your newly planted trees with a moisture meter, and water if dry. After your trees are established, they will handle freezes without any fuss.

An insulating blanket of shredded hardwood mulch will also help your trees survive the fluctuating temperatures more easily. Learn more about how to protect your plants from winter conditions.

Tree Trimming & Pruning

With the foliage gone from most trees during winter, now is a good time to prune since you can see the bare structure of the tree.

Look for crossing branches that rub up against each other and remove the smaller branch all the way back to the main trunk. Look for damaged or deformed branches. Thinning inner branches allows more light to infiltrate into the tree and for better airflow, especially important for fruit trees.

Learn more from the Arbor Day Foundation about proper pruning techniques.

Oak Wilt on Oak Trees

The best reason to prune in the winter is Oak Wilt, an infectious disease that attacks Oak trees. Oak Wilt is a fungus spread by flying sap beetles that carry the disease spores from an infected tree to a wound (an open cut) on a healthy tree. In the winter, the insect is more likely to be killed by freezing temperatures lessening the spread of the disease, which is a good reason to do your Oak trimming now. Apply a thin layer of ordinary black paint to Oak tree wounds (for every cut you make) to stop the spread of this disease. More info on Oak Wilt disease.

The Exception to the Rule

Crape Myrtles are an exception to the winter tree trimming rule. Many make the mistake of trimming or topping their Crape Myrtles thinking it will help their trees have more blooms the following summer. This practice is known as ‘Crape Murder’ – it doesn’t increase summer blooming, can lead to problems, and it just plain ugly! The only trimming Crape Myrtles need is the occasional removal of basal suckers, which you can do at any time of the year. Otherwise, DO NOT TRIM the tops of your Crape Myrtles.

Spring blooming trees should not be trimmed until after their blooms have faded. These include: Desert Willow, Eve’s Necklace, Mexican Buckeye, Roughleaf Dogwood, Rusty Blackhaw Viburnum, Saucer Magnolia, Smoke Tree, Redbud, and Mexican Plum.

Professional Help

Trees are a valuable part of our landscapes, and as such we would be wise to invest in their care. Sometimes this means turning to a professional. Arborists are trained and qualified to properly care for your trees with long-term plant health in mind. Professional trimming will also help protect the value of your home by keeping tree limbs from rubbing against your house and roof.

Why an Arborist

An arborist can provide expert tree services for everything from pruning, trimming and limbing up (practice of removing lower limbs over time for long-term health and aesthetics) to deep root fertilization, disease and pest diagnosis and control, and tree removals.

Last winter was been especially brutal on trees in North Texas, with ice and wind damage visible all over the metroplex. A certified arborist can help assess the damage and take necessary steps to keep your tree healthy. For more on dealing with trees damaged by winter conditions (and working with an arborist), check out The Dallas Morning News’s informative article on handling winter damaged trees.

A certified arborist will have credentials as well as insurance coverage. Additionally, they must meet standards set forth by their certification for such things as safety, training, customer satisfaction, so you can feel confident working with a certified professional.

Whatever you do, don’t hire a landscape maintenance crew, or worse, some guy with a chainsaw, and expect to end up with healthy trees. Remember you get what you pay for, so don’t skimp on tree care!

To find a qualified tree care professional or company in your area, visit the website of a certifying organization: Tree Care Industry Association (TCIA) or International Society for Arboriculture (ISA). I highly recommend working with an arborist for trimming of larger trees in particular, especially when safety can become an issue, and I can refer 3 reputable companies for handling your project.

Trees have always been a great passion of mine. They provide shade and cooling for our homes. They clean the air and water while offering food and shelter to wildlife. And trees create green spaces for our communities and a sense of place and history. Plus, they can simply be beautiful!

Start this winter: consider adding the perfect tree to your landscape or take good care of your existing trees, and you will enjoy all that they have to offer for many years to come.

Editor’s Note: This updated post was originally published February 2014.