Trees - Crape Myrtle (page 1)
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  (January) We moved from Russellville to Benton the end of July. The beds have not been kept up and are overgrown. I need help with the when and how much to prune. I have Crape Myrtle on the corners of the house and around the deck that are 18 to 20 feet tall. Can I cut these back to 8 to 10 feet? The Boxwood are four feet and the holly are eight feet high. How much can these be cut back and when? I also have overgrown azaleas. Shouldn't I wait until after they bloom before cutting and moving? I will appreciate any advice you can give.

  Why do you want to cut the crape myrtle back that much? If they have a nice shape and are growing well, and are not blocking a view, I wouldn't prune that severely. I think they are stunning small trees. If you need to prune, they can be pruned in late February or March. Selective thinning would be better than a general shearing. For the hollies and boxwoods, prune them back to the desired height. If that means taking off more than one third of the plant, try to get that done before spring growth kicks in--usually March or April is best. General light shaping can be done at any time. For the azaleas, wait until after bloom to prune and move.

  (January) Could you please tell me when is the correct time to prune Azaleas and Crape Myrtles?

  Prune only if needed. Azaleas should be pruned immediately after flowering. Crape myrtles should be pruned before new growth begins--typically late February through early March.

  (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) If you have time, I would sure like to know when you would recommend pruning Crepe Myrtles, Lantana, Coral Bells, Weigela, and Dwarf Maiden Grass. We planted all these plants last summer.

  There are several different types of plants you are asking about from annuals to perennials to woody shrubs. Let's start with the woodies. Crape myrtles bloom on new growth. If they need it, prune them before new growth begins in late Feb. Weigelia is a late spring bloomer, but it has its flower buds set now, so prune it after it blooms. All ornamental grasses benefit from a haircut before new growth begins--in late Feb through mid March. Before pruning, check to see how much new growth there is, and then cut as low as possible, without cutting into any new green. Coral Bells--or heuchera ( I assume you mean the perennial--not Coral bell azaleas) is a semi-evergreen perennial. Often you will have some cleanup to do in the spring before new growth begins. Lantana is a summer annual/perennial. In some parts of the state it comes back easier than in others. It is rare to see any lantana resprouting above ground. Usually it will come back from the crown, with the upper portions burned back by winter, so cutting back the dead foliage before new growth begins is beneficial.

  (March) Can I cut back the forsythia after it blooms? And isn't it time to cut back the Rose of Sharon bushes, crepe myrtles and butterfly bushes?

  Forsythia should be pruned after bloom. Remove one third of the old canes down at the soil line to encourage new growth. There is still time to prune Rose-of-Sharon, crape myrtle and butterfly bush, as all of these plants bloom on the current season growth. Try to do it soon since new growth is beginning.

  (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.

  (June) Four weeks ago numerous branches on our eight year old crepe myrtle trees began to sag to the ground. It appeared they were cut at the main branch. I removed them. Two weeks later new growth appeared. Today there were a few more cut and there was a white powder on several branches. I thought the cut was from some kind of insect but with this white powder I'm wondering if this is fungus due to the wet spring. How do I prevent more branches from falling?

We live on a lake and beavers like to chop off our crepe myrtle and dogwood trees at the ground. How do I repel beavers?

  I think you have two separate problems--possibly beavers or other animals, possibly cutworms, cutting the stalks; and powdery mildew-- a disease, causing the white powdery growth. Powdery mildew is extremely common on crape myrtles and the high humidity and mild temperatures we are experiencing are the perfect conditions for the disease. Once the temperatures heat up, the disease will slow down. If it is just a little white growth on the lower, fast growing branches, ignore it. If it is covering the tree, you may want to spray with a fungicide. The disease would not cause the branches to droop or fall off. For animal control, protective barriers are the only thing I know that will really help, unless you have a good dog.

  (June) I have some crape myrtles that have "babies" sprouting up next to them, about to bloom.  Is now a good time to transplant the "babies" or wait til autumn or next spring?

  Young crape myrtle seedlings can be moved whenever you choose, if you can keep up with the watering. If they are blooming, you may want to wait until they finish, but if you don't mind losing a few flowers, go ahead and get them moved. Crape myrtles thrive in the summer heat, so getting them established at their peak growing time is fine.

  (June) I have a crepe myrtle that was planted in my yard at the end of last summer (September) by a professional landscaper, and it does not have any buds now. It's about 6 feet tall and appears healthy -- it's got green leaves etc., but, there's not a single sign of a flower bud on it. I did prune it a little bit this winter -- probably in February or so, but I didn't do much more than cut some of the long wild stems off. Do you have any advice?

  I would say just be a little patient. While there are a few crape myrtles beginning to bloom, the majority are still not blooming. They do like hot, sunny weather to really kick into bloom, and it has been a little hit and miss so far this summer. It is not unusual for them to begin blooming in late June or even July. Sunlight is critical to blooming, so if your plant is in the shade, you may need to consider moving it. Sometimes young plants will also put on rapid new growth, which can delay flowering. Hopefully, you will see some flower buds soon.

  (July) We have a Natchez White crepe myrtle that we planted about 3 years ago. I have noticed this year that on the lower portions of the multi-trunks that the bark is pealing off, leaving a rather russet colored smooth trunk. Is a natural occurrence or do we have a problem? Its leaves are shiny and smooth and it's blooming and the blooms look good.

  Congratulations! Your crape myrtles have come of age. That is one of the beautiful parts of the crape myrtle--the peeling bark. Once the bark begins to peel, you should see wonderful shades of tans, reds or grays depending on the variety. In my opinion the bark is just as attractive as the flowers are.

  (August) My crepe myrtles need your help! Every year I fight powdery mildew on my crepe myrtles. Beginning early in the spring, I spray Immunox on a 10 day cycle. This year, in spite of rigorous effort, I have failed. My next door neighbor has a large un-kept crepe myrtle that spreads powdery mildew throughout the neighborhood so I dare not stop the Immunox. This summer another pest attacked my seven trees. Aphids and white flies infested the trees. At first notice, I contacted a local nursery and was told to spray Malathion on a one week cycle. I did. However, the aphids and flies thrived on the chemical and within two weeks, every leaf on every tree was covered top and bottom with aphids and flies. The leaves even became sticky with some sort of bi-product of the aphids. I returned to the nursery and was told to increase the Malathion cycle to every three days while continuing the Immunox on its regular 10 day cycle. I did. The results were the same, more mildew, more aphids, more flies. If that wasn't enough, the crepe myrtles then contracted some sort of black mildew which covered not only the leaves but also the bark on smaller limbs. So here we are approaching the end of the season. Some of my crepe myrtles have not bloomed even though they are well established trees instead, they are defoliating. My biggest concerns now are to ensure their survival and learn what must be done through the winter and into next spring to return the trees to health so we can enjoy full bloom next year.

  Wow! I am not sure seven plants are worth so much effort! You are definitely giving it the college try. Powdery mildew can be a difficult disease to control, but usually it is more of a problem if you allow it to get established, versus preventative spraying. Immunox is a good product. You may want to alternate with another fungicide to prevent the plants from building up a resistance next year. Pruning the plant to make it more open and airy can give you better air circulation and sunlight penetration. As to your insect issues: aphids are usually not difficult to kill but can multiply rapidly if you give them a chance. Whiteflies can be more of an issue. Both insects feed by sucking sap out of the plant and then they give off a sticky residue called honeydew. If the honeydew is present, you then get black sooty mold, which only grows on honeydew. Since this was your first attack of insects, you may want to wait and see if they reoccur -- not do prevention next year. If it becomes an annual problem, there are several options. One is the Bayer Advanced Tree and Shrub insecticide. You would apply it to the soil in March. It is systemic and can give you a season of control. With white flies, a second application is sometimes necessary in July. Di-syston is another systemic product which can work. While Malathion is a good product, the problem is that it is a contact kill product, meaning you have to come into contact with each insect for it to work. If you have large plants that have dense foliage, you probably are not getting thorough coverage. Those you miss, keep on going. Systemics work by entering into the plant itself. Orthene is a good one to use during the growing season if a problem arises. A combination of fungicide and insecticide is Orthenex, with Orthene and Funginex. As for this year, I would take a garden hose and hose down the tree thoroughly, trying to knock down the aphids and hopefully some of the honeydew. I personally wouldn't spray any more with pesticides this late in the year, especially as hot and dry as it is. Keep the tree watered and rake up any leaves after they fall. Try a different approach to pruning next February trying to keep the plant more open, and hopefully you will have a better season next year.

  (August) My Crepe Myrtle is about 7 ft tall and has not bloomed since I planted it about two years ago. It is in full sun. What can I do to make it bloom? It has beautiful foliage.

  Sometimes young plants will grow too rapidly and not slow down to bloom, while they are getting established. Don't give it any extra fertilizer and let it get a bit on the dry side. There is still the potential for blooms this season, but hopefully you will have blooms at least by next year. Crape myrtles thrive in plenty of sunlight and they love warm temperatures. They have really been spectacular in most parts of the state this year.

  (August) Help! Quite a few people I have talked with are having the same problem I am. No (or few and very late) blooms on our Crape Myrtles. Last year we had a few scattered blooms and those were very late. This year although my white one is in full bloom (but only the last ten days) the rose, red, and lavender ones either have NO blooms or flower buds, or have just two or three scattered ones at the top. Last year and prior years, I fertilized monthly. Bloom problems began last year. I wondered if the shrubs were putting too much effort into new growth rather than blossoms, so this year have not fertilized. Still no blooms.

  Crepe myrtles thrive in hot, dry weather. We have had more than the normal amount of rainfall this year (2004), and our temperatures have been mild, so we could put it down to that. Anything that makes crape myrtles grow quickly -- moisture or fertilizer, can slow down the onset of flowers. I have seen some plants blooming well, and others have also been impeded by powdery mildew. I don't think there is really anything you can do to alter their blooms this season, except be patient and enjoy the weather. Chances are, temperatures will heat up, and the rain will disappear, and the crape myrtles can regain their glory -- albeit a bit late.

  (August) Toward the end of last summer, I planted a small crepe myrtle by the driveway in the front yard. It gets direct sun only. It weathered the winter and came back nice and green this spring. However, it doesn't look like any new growth has appeared (it's about 2 feet tall), and it has had no blooms this summer. A larger plant of the same type (about 10 feet tall) has been blooming profusely. What can I do to help it produce blooms? I water it regularly, and fertilize it about every 3 weeks.

  If something is impeding the root zone, you won't get much new growth, and thus few flowers. Crape myrtles bloom on the new growth, and if you don't get much new growth, you won't see flowers. We do tend to have rocky soils, so you may want to dig it up and investigate.

Replanting in good soil can make a big difference, but you probably won't see the results until next summer.

  (August) I have a crepe myrtle that is healthy and doing well in a full sun area, but some of the flower heads seem to be dying prematurely. Should I cut them off or just let it go and trim in late February.

  Crape myrtle blooms have been spotty this year. You may have an attack of powdery mildew which has made them go early, or it could be all the rain! Deadhead the spent blooms -- clip them off beneath the flower head, and you should still have enough time for another set of flowers. Deadheading smaller plants (which are easier to reach) can give you several flushes of blooms each year.

  (November) My husband and I recently bought an older home in Conway. We have been experiencing some sewer issues with the home and it was suggested to us that we need to remove around 9 beautiful old crepe myrtle trees so we can lay new line. It seems the roots from these trees are very aggressive and have destroyed our existing line. My question is "Is there a way to transplant existing trees without causing serious trauma by removing abruptly?

  Crape myrtle trees in and of themselves do not have damaging roots. In fact, roots of a tree cannot damage sewer lines, unless there is a crack in the line. Then the roots will move in to go after the moisture, and may damage the lines more. Damage will be done to the roots if you are putting in a new sewer line, simply because they have to be dug up. There are ways of tunneling that can put in sewer lines, and underground cables of all sorts that are less damaging to the trees. If, however, you need to move them, take a root ball as large as you can manage and transplant. Fall is an ideal time to do this for hardy trees and shrubs. Crape myrtles should be mulched well and pruned in February. I often recommend waiting to move crape myrtles until February, so you can prune and move at the same time, but I don't think that will be an option for you.

  (November) Could you please tell me if I can go ahead and trim back my Althea's that have quit blooming and also my Crepe Myrtles. With the wonderful fall, I would like to get this done now instead of February when I usually do it.

  I have already seen several crape myrtles with a new "haircut" from recent pruning, but it is not our recommendation. There are two reasons I would not prune in the fall -- one is that you have a cut look on the plant all winter -- not as appealing to me as a full plant. Secondly, if we do have any winter weather, your plants will be more exposed to the elements. If you can, still wait until February for those plants that bloom in the summer. Keep in mind that many crape myrtles also have glorious fall foliage, that you don't want to miss out on!

  (December) Three years ago I purchased two Crape Myrtle trees. Since that time, they have not bloomed. When I bought them, they were in full bloom. Can you tell me the reason why they haven't bloomed in three years. Did I do something wrong when I planted them?

  I do hope the trees are planted in full sun, or at least a minimum of six hours of sunlight. If not, they won't bloom well, if at all. Another possibility is that they may be establishing themselves and growing. If the site is rich, you fertilize and water frequently, they may be in a growing phase, and not slowing down to bloom. Have they grown in leaps and bounds? If so, slow things down, by holding off on any more fertilization, let them get a little on the dry side, and see if you don't get some blooms next summer.

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