Iris leaf spot: how to spot, prevent and treat it disease
How do you spot iris leaf spot?
Brown to greyish spots with a darker edge appear over the leaves, spreading and running together in wet weather. The leaf dies from the tip down, while the rhizome stays sound.
How do you prevent iris leaf spot?
In autumn clear every leaf and all plant debris off the bed, because the fungi and the insects overwinter on that old foliage. Plant at an airy spacing and water at the base, not over the leaves.
What works against iris leaf spot?
Cut the affected leaves off as they appear and take them out of the garden, not onto the compost.
Which plant gets iris leaf spot? 1
Ornamentals 1
Sources: Clemson Cooperative Extension, University of Illinois Extension
Checked on 17 August 2026.