Groundcover - Ajuga
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  (August) Attached are two photos of my ajuga in the front (east) yard. They have early morning and late afternoon shade and have done well until about a month ago. They are watered every other day in the very early morning for about 15 minutes each watering. Can you tell me what is going on and what I can do to stop the process.

  Your ajuga plants appear to be suffering from crown rot. Crown rot is a fairly common problem in ajuga, especially in areas that are not well drained. The problem thrives in warm, wet conditions, so we have had the ideal year for it. Plants that are infected will start "melting" away. You will see wilted plants, and if you pull one up, the crown is usually soft and rotted, and the root system is typically brown and slimy. If the plants are left there, the disease forms a hard fruiting body called a sclerotium which looks like a small mustard seed, which can persist in the garden indefinitely. The key for control is to get rid of diseased plants and the surrounding soil as soon as you see it. Cut down on the amount of water you are putting out. Use a preventative fungicide such as Terraclor for those plants not affected in the garden (PCNB - pentachloronitrobenzene is the chemical name). Follow label directions. If the problem persists, you may want to introduce some other groundcovers that are less susceptible in this area.

  Last year in the spring I planted ajuga in a mostly shady area of the yard. This spring they spread into a beautiful mass. The area is watered twice a week since I have new zoysia in the area also. In the last month the plants have begun dying. The plant begins dying at the center of the area from which the plants multiplied in the spring and then the "destruction" spreads out to the plants it produced. I now have big gaping dead patches and am afraid by the end of summer not much will be left. There are no visible insects or evidence of chewing on the leaves--it simply appears to dry out and die. Is there anything I can do to stop this?

  It sounds like your plants are suffering from crown rot, a serious problem with ajuga if it is overcrowded or in heavy wet soil. Dig up the damaged area, and try to cut back on watering in the ajuga bed if possible. A soil drench of Banrot or Cleary's 3336 (both fungicides) should help to stop the spread. But correct the moisture problem.

  Two years ago this past spring, we bought quite a bit of ajuga to cover an embankment. It did fine until the hot weather began, and we noticed round spots on the leaves and a white substance on the roots, and then the plants started dying. We lose about three fourths of the plants every summer. The ajuga comes back every spring, but we have about given up. Would it be possible to pull up the ajuga and plant violets? We have several volunteer violets in the ajuga, and they don’t seem to be affected. Thanks for your help. (Batesville)

  How much sunlight does the ajuga get? If it is exposed to direct afternoon sunlight, and it has a sloped bank (which makes water retention hard) it could be experiencing heat stress. Ajuga does not spread as quickly as some other vining ground covers. The white substance has me confused. Any diseases that I know ajuga gets, kills the plants entirely--they would not regrow again the following spring. You may want to take another sample in to the county extension office for them to mail to the plant disease diagnostic clinic to see what you have. If you have shade, the violets should be fine, but they won’t cover quickly. You may want to use a vining plant such as vinca or ivy. Wintercreeper euonymus can grow in either sun or shade and would be another option.

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