Are ants responsible for annual flowers that are dying?


I have a happy, healthy bed of annual flowers- cosmos, Mexican sunflowers, zinnias, verbena. I moved a wooden plank into the garden to create a border for the bed. I noticed there were small ants in the board. Since then, my annuals have been wilting and dying and the base of the stem of them is girdled. Are the ants responsible for this? Why do ants do this? What could be another explanation? Also, it’s not all the annual plants that are dying, only one at a time. As soon as one dies, it seems they love on to the next. 


Donna R. Coffin,  Extension Professor

Several of us have been looking at them and it appears there may be a couple of things happening. Drought stress and a leaf disease. The stress of the drought can make plants more susceptible to disease. Pulling up the affected plants and disposing of them at the landfill will help reduce the inoculum of the disease. Incorporating more organic matter in the soil and using mulch and supplemental watering could help next year’s garden. We do not think the ants have caused the problem, but the few you have observed may be using these plants as a source for moisture.

Hopefully your garden got a little of the rain that has been falling in the state the past few days.