If you have been putting off the big trim, December and January are the weeks to book it. Texas A&M AgriLife Extension puts it simply: “December and January are ideal times to prune trees because they are not actively growing.” In Houston that window comes with a bonus and a deadline. The bonus is that it is the safest time of the year to cut an oak. The deadline is February 1, when the oak season closes.

Why winter is the best time to prune

A tree in December is resting. The leaves are off most hardwoods, or thinning, and the sap is not running hard. Three good things come out of that.

You can see the whole tree. With the canopy open, crossing limbs, deadwood, weak forks and branches rubbing the roof are easy to spot. In July they hide behind a wall of leaves.

The cuts have a calm few months to close. Insects and fungus are far less active in a Houston winter than in our wet, warm spring. A clean cut made in January starts closing as soon as the tree wakes up.

The tree is not pushed into new growth. A heavy cut in early fall can wake a tree up and send out tender shoots right before a cold snap. In mid-winter the tree simply holds until spring.

The oak deadline: done by January 31

Oaks are the reason December and January matter so much here. Texas A&M Forest Service asks Texans to avoid pruning or wounding oaks from February 1 through June 30, because that is when the beetles that carry oak wilt are most active and a fresh cut is most likely to let the disease in. Its oak wilt flyer gives those exact dates.

So for live oaks, water oaks, post oaks and red oaks, the winter window is the last good time to prune until July, and the Forest Service suggests waiting out the summer heat after that too. Our oak trimming guide lays out the whole year month by month. One rule holds in every month: paint every oak cut right away.

What to prune this winter

Dead and broken limbs. These can come out any time of year, but winter is when you can find them all.
Branches rubbing the roof or hanging over the driveway. Winter is the easiest time to set clearance before spring growth closes the gap again.
Crossing and rubbing branches inside the crown, before they wear through each other’s bark.
Weak forks and competing tops on younger trees. A small cut on a young tree now saves a big one later.
Low limbs you want lifted over a lawn, walkway or play area.

What to leave alone

Don’t top a tree. Cutting the whole crown back to stubs brings back weak, crowded sprouts and shortens the tree’s life.
Don’t take too much. Leave most of the living canopy in place in any one year. A tree makes its food in its leaves.
Don’t flush-cut. Cut just outside the branch collar, the slightly swollen ring where a limb meets the trunk. Our guide to proper pruning technique shows the three-cut method for heavy limbs.
Don’t wait until February on oaks. Once the calendar turns, oak work stops until summer unless a limb is a danger.

Pines are different

Loblolly pines, the tall pines across north Houston, The Woodlands and Magnolia, rarely need shaping. What they need is dead limbs out before they fall, and clearance from the roof. If a pine is browning from the top down, that is a different conversation; read how to tell normal fall needle drop from a pine in trouble.

When to call a crew

Small deadwood you can reach from the ground is a reasonable weekend job. Anything over your head, anything near a power line, and any big limb over the house is not. If you want your trees set right before spring, or you have oaks and want them done before February 1, we’ll walk the property, tell you what each tree needs, and give you a clear written number before any work starts.

Source: Texas A&M AgriLife Extension, Williamson County, “Time for Tree Maintenance”, November 8, 2023; Texas A&M Forest Service, Oak Wilt in Texas.

Book your winter pruning:

Winter Tree Pruning in Houston: Why December and January Win