I noticed a couple soft rhizomes in my iris bed. Does that mean I have borers? I dug them up and did not see any borers in them. Thanks for your help.
Are you letting the soil dry out between deep waterings? Have you had iris a long time and is this the first time it's happened?
We don't have borers, thank heavens, here. The FAQ may have information on that. Or a search will bring up old posts on the subject.
They can get rot which turns the rhizomes to mush and has an awful smell. Keep them on the dry side and see what happens. If they get really soft dig and trash.
Now I see your other post (leaf spot) and that you are having rain. Send some this way!
Good drainage is essential to beardeds. The tops of the rhizomes should be exposed rather than covered with dirt or other plants. Are they too deep?
It could also be just the mother rhizomes rotting away. Is there a horrible smell with the rot? If there is then it is more than likely bacterial soft rot.