|My Iris have leaves that curl and then hook presenting a deformed appearence. The UGA extension checked some samples and said no disease. What do you think? Soil test good.|
|If your extension service ruled out diseases, the problem could be cultural or it may the result of insect feeding. Extreme aphid damage may cause leaves to curl or bend in an unnatural way because the side of the leaf with the most damage has lost the most fluid, and so is less turgid than the other side. The unequal pressures cause the leaves to curl. It's possible the aphids fed then left the area and the only sign of their visit is the curled leaves. A microscopic exam of the leaves will expose the feeding damage or you may be able to detect it by using a magnifying glass and looking at the undersides of the curled leaves.