They might be planted too deep. You can lift and put more dirt in so you can see the rhizome but you might or might not loose bloom this year. Normally iris are divided 6 weeks after bloom in OR that is July or August.

You can try the above recipe for the leaf spot if you do not have alot that will do some good.

Hope this helps

Denise

Are they crowding each other? If so, then I'd replant them. They'll bloom better and giving them a little more space might help with the leaf spot, too. As far as not seeing the rhizomes, some irises tend to grow their increases a little deeper than others, so as long as they're right below the soil surface, that might not be a big deal. If they're deeper than an 1/2" - 1", I'd raise them up for sure.

Waiting until about 6 weeks after they bloom is a good time to divide and move them. Gives them time to slow down growth into a bit of summer dormancy, but gets them going before they get going again in fall. At the latest, replant them 6-8 weeks before your first fall frosts.

I used a baking soda spray when I lived in VA for leaf spot, and it helped some. I also tried a chemical spray once that didn't do much for me. Most important is good air circulation, removal of diseased foliage, and prevention of soil splashing up on the foliage (a very light layer of pine straw works well).

I did read a while back that corn meal has natural anti-fungal properties, and some rose growers were trying sprinkling that around their roses and making sprays with it with some success. But I haven't tried it - since moving away from humid VA, I haven't had as much of an issue with leaf spot.