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Thursday - September 04, 2014

From: Sugar Land, TX
Region: Southwest
Topic: Pruning, Shrubs, Trees
Title: Pruning Texas Mountain Laurel
Answered by: Anne Van Nest

QUESTION:

I've had a Texas mountain laurel for 4 years that's being trained into a tree. I think it was a 3-year old tree when I purchased it. Unfortunately, it has suffered from overwatering, and the two main branches are 8-10' tall and are very top-heavy. The lower trunk is about 1 1/2" in diameter. In the first year, it was planted in poorly draining soil, but was relocated to a well-draining spot with alkaline soil and compost mixed in the second year. I fertilized it once two years ago, but haven't fertilized it since. Having now learned how to take care of it, the excessive growth has slowed greatly in the past year. It hasn't bloomed well historically (presumably due to the aforementioned abuse), but it looks like it has put on blooms for next spring. Is there any hope for it? Could I prune some of the length off the tallest branches? That seems counterintuitive, but it's so top heavy that I don't see the trunk catching up with the excess top growth. Thus far, I've pruned off some of the lower branches, but that's it. I'd appreciate any help you can offer. Your previous posts on Texas mountain laurels have helped me to understand proper care, but I haven't found specific direction about how to address the top-heaviness. It looks healthy and has nice foliage otherwise. A few leaves have died off this spring, but that's been minimal.

ANSWER:

You can prune your Texas mountain laurel (Sophora secundiflora) so that it is not so top-heavy, but don't prune out more than 1/3 of the shrub during one year. Janice Kvale answered a previous Mr. Smarty Plants question about pruning Texas mountain laurel shrubs and made some great suggestions that have been included below.

Sophora secundiflora (Texas mountain laurel) is a wonderful evergreen shrub which breaks forth in February and March with showy purple blossoms whimsically smelling like grape bubblegum or perhaps Kool-Aid. But you know all that so let's get to the crux of the question. This is not a shrub that usually requires pruning, so is there a good reason to prune your specimen? Let's assume there is and you want to do something about it. Those blossoms appear only on year-old wood, so you may not want to prune until after the bloom period. If you prune after blossoming to preserve the bloom for next year, you may find pruning stimulates increased blossoming. The classic rule on pruning is prune during dormancy and, in Texas, during the winter (you may lose the blossoms for the next season) or during the hot summer.

First, envision how you want the finished product to appear. Mountain-laurels may be shaped into bushy shrubs or taller trees. The U.S. Department of Agriculture Forest Service describes Sophora secundiflora (Texas mountain laurel) as averaging between 15-25 feet tall with the potential of reaching 50 feet high! On the other hand, the bushier they are the better screens they make. For a tree-like appearance, encourage height by pruning out the lower branches leaving between one and three trunks. With this choice, there is increased maintenance in keeping the suckers at bay. For a shorter, bushier appearance, trim the upper branches to discourage height. Because this shrub is slow growing, it may take time (think years) to achieve the look you are striving for. Unless you want faster growth (which may require more need to prune), do not fertilize the shrub or the grass around it.

Prune no more than one third of the shrub at a time, taking first any dead, broken or diseased parts. Then take out the thin, spindly branches with narrow crotches. Cut the branches back to the point of origin or next lateral branch. Pruning paint is not necessary as there are few or no diseases to cause concern. Also, you can always hire a landscape professional to advise you on shaping the shrub and doing the pruning. Our Suppliers List may help in finding such a person.

From the Image Gallery

Texas mountain laurel
Sophora secundiflora