Express-News

By Calvin Finch, PhD, SAWS Conservation Director, and Horticulturist

Saturday, January 10, 2004

IT’S PRUNING TIME

It will soon be prime pruning time in South Texas. January is a good time and February is the best time to prune most plants. Do not prune for the sake of having something to do. Prune to control plant size, remove unsafe branches, remove dead wood and, in some cases, to shape or maximize production of high quality fruit.

Pruning paint is not necessary except in the case of live oaks and oaks in the red oak family (Schumardi, Texas red, Spanish, etc.). Paint the wounds over one-inch in diameter to protect the plant from oak wilt.

 Crepe myrtles are probably the species that is most savaged by our urge to prune. They bloom on the new wood that grows in the spring so the theory is that heavy pruning stimulates lots of new wood. The theory is correct but to get the maximum bloom you do not need to hack off the tops to leave stubs. If your crepe myrtle is relatively young and growing in full sun, it may put on enough new growth that pruning is unnecessary. In other situations, some of the thinning cuts we describe later in this article for peaches will do the job without leaving an ugly plant.

The good news is that crepe myrtles are very forgiving. They recover from the worst pruning and still bloom. Prune crepe myrtles in February or even March. They are slow to begin growing in the spring so you have extra time.

We prune peaches and plums every year to reduce fruit load (avoid breakage), to open the middle of the tree to air and light, to control size, and to stimulate new wood growth. Prune in January or February to leave a tree with an open middle about 8 feet tall with all dead and wounded wood removed. Also remove the suckers growing directly from the roots and the water sprouts. Water sprouts are the branches growing straight up from the middle of the tree with very few buds.

Thinning cuts are the best. A thinning cut occurs when you follow the offending branch to its origin on another branch and cut it there. Hedging cuts are less desirable because they disrupt the tree’s hormonal control. Hedging cuts are cuts that remove part of a branch, a cut that leaves a stub.

Pears are pruned differently. The suckers and dead wood are removed but we do not try to open up the middle by cutting. Instead, try to spread the branches with spread sticks (1-inch by 3-inch with notches on each end). Spread side branches to a more horizontal orientation; 60 degrees is good.

If you cut on pears too much it kicks them into a vegetative state. You get branches that reach to the sky but no fruit. That is also why we limit fertilizer use on pears.

Apples are somewhere in the middle between pears and peaches. We try to open up the tree with pruning but not to the open vase shape of peaches or plums. Leave the central leader and thin out the tangle of branches growing off of the leader so that the finished product looks like one of the circular steel staircases—well-spaced branches around a central spine.

For those of you who do better with diagrams, go to the website plantanswers.com or contact the Texas Cooperative Extension at 467-6575 to receive publications that have pruning diagrams.

Old-fashioned roses often are only pruned when they get “out of hand” but the modern hybrid tea roses are blooming machines that do best when they are pruned every year. Prune them in late February. The peach model works well for roses as well. Select three or four main stems that are finger to thumb size in diameter. They should be spread around the plant arising above the graft and radiating at a 60-degree angle. Remove everything inside this frame so the middle is open to air and light. Also remove wounded wood, tangled wood, and wood growing inward or straight up. Old wood should also be removed in favor of green young wood. Do not be afraid to cut; it is hard to over prune a modern rose.

Reduce size on hybrid tea (modern) roses to about 24 inches with the cut just above and outward facing bud. The new growth will emerge from this bud and maintain your open vase shape.

Exceptions to the February pruning recommendation include the early bloomers and conifers. Prune Texas mountain laurel (if it needs it), climbing roses, ornamental fruit trees, and other early bloomers after they bloom. Prune conifers after the first flush of growth is complete and only remove one half of the new growth.