Ask Burton: Q: My crape myrtles are covered in a sticky mess, and there’s webs all over the plant. It looks awful! What’s going on, and how do I stop it?

A: Aphids are all over crape myrtles in the Metroplex right now, and they’re the cause of this mess.  Aphids suck sap from newer growth, and the shiny, sticky residue they leave (called ‘honeydew’) is mostly sugar water.  The webs are those of ordinary spiders, feeding on the aphids, not the plant. There’s a lot of this going on right now, but don’t worry!  Your crape myrtles don’t like being fed on, but the aphids won’t cause much damage this late in the season.  When the leaves drop, the problem will end for the year, and that won’t take long to happen.

If you do nothing, your crape myrtle will be fine next year.

Now, if the sap is raining down on your cars in the driveway, your concrete, or the webs are just generally so unsightly that you want this problem gone as soon as possible, this can happen.  Most common insecticides labeled for use on shrubs will work – spray every four days until you get control of the problem. Two sprayings will generally get the job done!  You don’t need to spray until the problem is eradicated; just spray a couple of times to keep the mess down to a minimum until the leaves fall.

To prevent pests on your crape myrtle next year, we’d recommend using our Bonide Systemic Insect Drench next spring after the plant has come fully into leaf.  This insecticide will work its way through the plant to protect your shrub for four to six months after application.  It’s a great way to head this problem off before it happens.