Q: Is it too late to divide bearded iris in August?
A: My rule is that you can divide iris and daylilies anytime between the last blooms and the first frost. Now is a fine time.
Dig them carefully with a spading fork and shake the dirt from the rhizomes (thickened roots). Clip off any that appear dry, rotted or unhealthy.
Plant the rhizomes and attached foliage in a sunny bed into which you’ve mixed lots of soil conditioner. There is no need to clip the leaves.
The roots should be barely covered with soil after you water them in. You’ll enjoy plenty of gorgeous blooms next May.