When I was potting up some iris yesterday I noticed black spots along the top of all the iris I got in a recent order (not Superstition). It was the area just in front of the fan. Some of the larger rhizomes had a solid black band. I think it is mold. I washed bleach and water over them and sprinkled Comet on them. On ones with just spots the bleach seems to have removed all the mold but those with black bands still had some.

Should I dig these all up and dip them? One of the rhizomes is a iris that is hard to find so I want to not lose it. The spots are on every iris I got in the order. Never had this problem before.

Suggestions?

I think, if it was me, I'd just leave them be, if they are already in the ground. Maybe a squirt of fungicide might be in order, and, of course, keeping a close eye on them.

That's different. I think Arlyn is right, usually the black powdery stuff is a fungus. On corn sometimes you get what's called smut, and it's a black powdery growth. I've never seen it on an iris though.

I had some on the cut rhizome tissue I received earlier in July. I think it was from the drying. My garage is always steamy in the summer and I've never had or seen this happen with or without my fan running when I've shipped.

I dipped and wiped it mostly off and planted and they're all secure and growing fine. Hmmm

I have it too!!! I'm just leaving it alone those because so far it isn't doing anything obvious to the rhizomes besides freaking me out. It isn't fuzzy or soft. I'm worried that if I scrape it off I might introduce the tissue to infection.

Lestv said:When I was potting up some iris yesterday I noticed black spots along the top of all the iris I got in a recent order (not Superstition). It was the area just in front of the fan. Some of the larger rhizomes had a solid black band. I think it is mold. I washed bleach and water over them and sprinkled Comet on them. On ones with just spots the bleach seems to have removed all the mold but those with black bands still had some.

Should I dig these all up and dip them? One of the rhizomes is a iris that is hard to find so I want to not lose it. The spots are on every iris I got in the order. Never had this problem before.

Suggestions?

Leslie, are you able to post a picture of it. Sorry, I don't have anything useful to tell you, but I'd like to see what it looks like for educational purposes

I have had this stuff. Doesn't always "wash" off easily or sometimes not at all. I agree with Arlyn and others to generally leave it alone. Most of those with it had been a long time in shipping and probably were not completely dry. Of course if it were completely dry the fans would be all shriveled as would the rhizome. Some did not grow the following spring, but I don't attribute that to the mold, but to the late planting with less than 6 weeks to first killing freeze, so roots had less time to take hold. None of the rhizomes became mushy.

This is what mine looks like. I don't know if it's the same thing you all are talking about. The tissue hasn't eroded, but the black stuff came up where the old tissue was pulled away when I ripped off a dried up fan.

Dachsylady86 said:This is what mine looks like. I don't know if it's the same thing you all are talking about. The tissue hasn't eroded, but the black stuff came up where the old tissue was pulled away when I ripped off a dried up fan.

You are quite right that the black stuff is dry. The spots wash off, the band doesn't. I will keep a watchful eye on them and go take a picture too. Thanks.

I get that every year here on my new ones. Me think it's the humidity. I leave it alone and all is fine.