|I planted three crepe myrtles and three Anthony Waterer spireas as new landscape plants in a bed next to my driveway with a southern exposure. The soil is sand, but has been amended with compost and peat and the bed is mulched with bark. This fall the crepe myrtles lost their leaves and the spireas have turned brown. I battled spider mites last season throughout my new landscape plants. Could spider mites be the problem or is the loss of leaves normal for these shrubs. If it is normal, should I cut them back in spring to encourage new growth?|
|Both of these plants are deciduous, meaning they normally lose their leaves in the winter.
Crepe myrtles are usually pruned to live wood in early spring to remove any wood killed back by the cold weather and also in some cases for shaping. However, a new plant would require only a minimum of pruning. They bloom on new wood of the season, so prune early and then stop.
Summer flowering spireas such as "Anthony Waterer" can be sheared lightly in spring to encourage a tidy shape, and can be sheared lightly again after the first flush of bloom. Older shrubs can have some of their oldest branches removed at the base of the plant to encourage new vigorous growth, but yours will not need that treatment for at least several years.
Without seeing the plants it is a bit difficult to guess if their defoliation was truly normal or as a result of drought stress or mite damage. Since these are new plants water as needed to make sure that the soil stays moist next summer (check the soil with your fingers to see if it is moist) and watch carefully for any signs of mites so you can stop that problem before it becomes so serious. If it looks like the mite problem is starting again you might want to check with your County Extension (722-7721) to make sure that is indeed the problem and verify the most up to date control measures suggested for them in you area.