You can do it either way. If it's a really bad infestation I usually start trimming for the looks of the plant. Today I was pulling off the outer leaves that have dried up. Dreamin' of spring bloom.

Thanks for your info iris gal.

This has been a big issue for me this year too. During the cool very wet Spring, infections were so bad I lost some clumps, and others were set back severely.

Most have made a good come back. I am trying to figure out how to be preventive. I replaced the soil for the ones that had the worst infestations. Currently I am spraying once weekly with neem oil, hoping the active ingredients will soak into the rhizomes and reduce further infection. New growth is green and spotless, but I imagine when chilly rainy season returns that will not be the case.

They are in raised beds. Drainage is good. Air circulation is good. I removed other plants that might impair circulation or shade the irises.

Not sure what else to do. I would like to give them some fertilizer for a boost of growth, but I fear doing so last year promoted fungal infection, so I'm not doing that now.

For old leaves with a few spots, I am leaving those on and spraying with neem. For leaves with a lot of spots, I removed them.

I've never tried Neem. Is it recommended for iris leaf fungus?

One year the leaf spot started at bloom time so I used the rose fungicide on hand. Repeat applications per directions did prevent spreading. It inoculated the unaffected areas of the leaves. We were having hotter summers back then.

Also one bad year doesn't mean a 2nd bad year. Unpredictable.

Iris gal, I have not seen a recommendation of neem specifically for bearded irises. This summer I have been spraying them weekly in hopes they will build up resistance by absorbing the antifungal agents into their leaves and rhizomes. I dont know if it will work.

I used to use neem oil for rose leaf spot and mildew and it worked very well. I read it is safe for humans and also that some people use it for skin and toenail fungus problems. So. it seems pretty safe.

Some plant leafs get badly burned with neem. it almost killed my okra. But the iris leaves look like they have no damage at all, and they are growing now.

I garden organically and I dont want to use toxic chemicals.

I hope it works.

Iris gal, I have not seen a recommendation of neem specifically for bearded irises. This summer I have been spraying them weekly in hopes they will build up resistance by absorbing the antifungal agents into their leaves and rhizomes. I dont know if it will work.

I used to use neem oil for rose leaf spot and mildew and it worked very well. I read it is safe for humans and also that some people use it for skin and toenail fungus problems. So. it seems pretty safe.

Some plant leafs get badly burned with neem. it almost killed my okra. But the iris leaves look like they have no damage at all, and they are growing now.

I garden organically and I dont want to use toxic chemicals.

I hope it works.

Hi Bear,

I seldom use chemicals. The bearded iris leaves always look pretty tired in summer. Then, here in mild winter climate, new leaves begin emerging about this time. They are fresh and healthy looking. I've never seen leaf spot from fall to spring. Actually had next to none this year. If it comes next year I'll live with it because it does not kill. Iris rot does, The 2 may be present at the same time but it's the rot that is the death threat. Aren't we lucky we don't have iris borers?!

Thanks for information about Neem oil being effective against rose leaf spot and mildew. Evelyn could use a spraying.