Pruning - Crape Myrtles
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  (January) Can you please tell me when to trim my azaleas back. I know they should be trimmed shortly after they bloom but when is best and is it ok to shape them with electric shears?

  I think you have the right idea. To take a soil test, get a pint of soil from the areas root zone. Since we are testing a specific site, you don't have to take multiple samples of soil and mix them together, as we would if testing the entire yard. For this, test the good area and the bad area, then compare. Take the samples to your local county extension office. You should have your results back in approximately two weeks. Also check the physical site characteristics--drainage, rocks, low area, etc.

  (January) I know you have addressed this issue in your column but I need information on pruning or not pruning these trees. In our neighborhood, we planted two big crepe myrtles last spring. There are people in my neighborhood that want to prune them in the style known as "crepe murder."

  This is probably the number one question I get both in the newspaper and on the radio. There are thousands of crape myrtles varieties with a variety of eventual heights. If you own a standard crape myrtle that has the potential to become a tree, then let it grow and become a tree. You do want to do some shaping from time to time to get a nice shape, but severe butchering keeps them from maturing. Many crape myrtles have interesting peeling or exfoliating colorful bark which if allowed to grow, you would eventually see. If you have the dwarf or miniature crape myrtles, they need shearing each year to keep them looking attractive. 'Crape murder'--shearing the standards back to 3 or 4 feet makes them grow rapidly each year, and produce large flowers, but these large flowers on weak new growth make them top-heavy, and every rain has them dragging the ground.

(January) We continually get questions about crape myrtles, and last week we had a question and answer on pruning them. Here is some extra information that was sent to me from Little Rock's Urban Forester Pete Rausch:

They should know that winter is far from over, and that early pruning of crape myrtles could result in frozen buds and dieback if we have severe weather. Also, property owners in Little Rock can not prune street-side crape myrtles lower than 6 feet (Little Rock ordinance) because the dense sprouting can limit a driver's view of oncoming vehicles of sidewalks, driveways and street intersections. (This is good advice even in communities without an ordinance) Also, crape myrtles, large shrubs and trees should be planted no closer than 30 feet from an intersection because of the same "line-of-sight" and the possibility of blocking stop signs and/or traffic signals.

As mentioned last week, another benefit of not pruning crape myrtles too low is that they will take on a larger "tree form" which is very attractive and healthier for the plant. As a matter of fact, the state champion Crape myrtle "tree" is in downtown Little Rock. It's multiple stems are greater than 10 inches in diameter, 30 feet tall and has a crown spread of nearly 30 feet.  When it is in bloom it's a spectacular mass of pink.

  (February) I have always pruned the crape myrtles in February, and prune them at the same place each year. They are 7 years old, and grow to 15 or more feet in the summer. I prune them to about 8 to10 feet. I gathered from last weeks column that it is not necessary to prune them at all, only for shape. I thought they only bloomed on new growth, and that is why I have always pruned them. What are your thoughts on this?

  While it is true that crape myrtles bloom on the new growth, they should continue to put on new growth each year, if they are healthy plants. The older they get the slower the new growth is, but the wood simply gets stronger. You are not ruining your plant by pruning them back to eight to ten feet in height--you are still allowing them to be trees, unlike those who go back to four feet in height. You may want to gradually shift your cuts a bit higher if you have good branching. Plants that don't have heavy pruning often have smaller blooms, but usually more of them, and they stay upright. Plants that are pruned severely, produce rapid new growth which often gives you too much foliage, and the large flowers often cause the limbs to bend under their weight.

  (February) With the crazy swing in weather we have been having here in Conway is it too early to prune Crepe Myrtles and roses?

  Our recommendation stays the same -- wait until late February to prune both roses and Crape myrtles. Hopefully, by then, the bulk of cold weather has passed, and our plants should have suffered what winter damage they were going to. Crape myrtles tend to be one of the last plants to begin leafing out in the spring, so pruning even into March is not bad. We like to get pruning done before new growth begins, since they bloom on the new wood. Roses many times have begun active new growth before we prune--especially in mild winters, but we still recommend waiting until the end of the month. It is better to err on the side of safety.

  (March) I recently purchased a house with several large crepe myrtles in the yard. A number of the limbs are very large (half-dollar size) and have forked where they were cut back in the past. Can I cut below the fork and if so, how far below the fork can I cut these?

  I prefer to let crape myrtles grow up and become trees. Is there a reason why you want to cut beneath the fork? You will see knobby pruning all over town, but this results in a huge burst of sprouts, which will then be top-heavy when the blooms come on, and tend to cascade down. In answer to your question, yes they can be pruned lower, but question your reasons why before doing so.

  The question I need answered is: Are crepe myrtles supposed to be pruned yearly? I think I read somewhere they should not be pruned because it could lead to disease problems, yet everywhere I see them cut. Please clarify this for me.

  Crape myrtles do not have to be pruned yearly once they are the size and shape you desire. Many people butcher their crape myrtles every year by cutting them back to three of four feet off the ground, in search of larger flowers. In many cases, this leads to rapid new growth–and lots of it, which can lead to more problems with powdery mildew. It also makes for weak branches which often weep down under the weight of the blooms. While pruning is not really linked to disease problems, severe pruning is not a great practice. If you have standard varieties, I recommend allowing them to become trees.

  When we were in Little Rock a few weeks ago, we admired the crape myrtles that grow like a tree, rather than a spreading bush. Is this accomplished by pruning? When is the correct time to do this?

  Crape myrtles vary in shape and height based on the variety as well as how they are pruned. There are dwarfs up to standards. If you have a standard, choose one to five main stems, prune everything else out. Then each season, gradually shape these branches, allowing for a full upper canopy. Prune off suckers and sprouts as they appear. Pruning is best done in late February. Winter damage may occur some years, especially since you are in the northern part of the state.

  I planted a row of 8 crape myrtles...they are small (their stalk is about the size of a lead pencil). The untrimmed height now is about 4 feet. Are they too young to trim? I want them to eventually provide a privacy fence between five and eight feet tall.

  They are not too young to trim. When crape myrtles are young is the time to get their branching structure formed, and then the need to prune every year should decrease. Trim to encourage a strong network of branches, and to get stronger branches. If you leave a lot of then twiggy growth, the resulting branches will also be weak. Do your pruning any time between now and the time new growth begins.

  We had some lovely nine foot tall crape myrtles in front of our office, but they got butchered before Christmas by the landscaping crew. They are now about one foot off the ground. I am outraged, but was told this is the annual pruning that is needed. I have never heard of such a thing, but would like your opinion. Do crape myrtles need yearly pruning and this much, and is December the proper month to do it?

  No and no!! If you have standard crape myrtle varieties, I like to see them grow into trees. They have wonderful peeling bark with age, and although individual flowers may not be as large, they are more numerous, and stand upright instead of weighting the branches down. Many people in the south keep their crape myrtles pruned to a height of five feet or so, and I think that is too much–one foot is obsessive–and possibly damaging. The proper time to prune crape myrtles is late February, before new growth begins, and after winter weather has passed. By pruning in December, and that severely, it could make the plants more susceptible to winter damage, should cold weather occur. Try to encourage the caretaker of these plants to allow them to grow, and limit pruning to thinning cuts and shaping.

  Is it too early to trim back crepe myrtle bushes? I trim them every year, but I notice around town that some people have already trimmed them back for this year and I generally wait until close to springtime. 

  Many people begin pruning their crape myrtles as soon as they lose their leaves in the fall. While this can be done, I too, prefer to wait until late February. There are two reasons--one I think they look more attractive, and secondly, if we should by some chance get any real winter weather, the plants have more protection, than if they have already been pruned back. Crape myrtles have been known to be winter killed, but not in the close past, due to our mild winters. One extra word on pruning crape myrtles–if you have standard sized plants, don’t butcher them by severe pruning. Let them grow up and become mature, attractive trees. Do prune off suckers, small growths, and make some thinning cuts.

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