I noticed a couple weeks ago that one iris was developing yellow spots and patches. As it seemed to be just one plant and it was an "accidental" that I didn't order, I just kept an eye on it... until I got busy planting my new daylilies for a few days. When I checked on this iris again, here's what I'm seeing:




Is this Leaf Spot? Or something else? In the second picture you can see the plant next to it is now also showing some spots. None of my others seem to be affected.
Any advice would be appreciated!

This does not look like leaf spot to me. Leaf spot has multiple rust-orange colored spots. Has there been a change of temperature recently where you live? Sometimes heat can cause spotting and browning of the foliage.

If you are worried about this, you can always cut the spotted leaves.

MrsMud said:I noticed a couple weeks ago that one iris was developing yellow spots and patches. As it seemed to be just one plant and it was an "accidental" that I didn't order, I just kept an eye on it... until I got busy planting my new daylilies for a few days. When I checked on this iris again, here's what I'm seeing:




Is this Leaf Spot? Or something else? In the second picture you can see the plant next to it is now also showing some spots. None of my others seem to be affected.
Any advice would be appreciated!

It's DEFINITELY NOT LEAF SPOT. I have a lot of it in one of my beds. I feel like THE QUEEN OF LEAF SPOT.

Last year I had those white-ish leaf marks, like fade on denim? They were on the leaves to my Melanie Irises. I had/have some soil nutrient deficiencies that might have contributed to that. Melanie has been in the same spot for 5 years.

So, I'd ask you, how is your soil? Has that iris, or something else, been there a few years? Consider amending your soil. I have not yet seen these marks this year, and I didn't do anything drastic.

Hope that eases your mind.

Thank you both for your input. I'm glad it's not leaf spot (and hopefully not something worse!)
I guess we have had a somewhat rapid increase in temperature the past couple of weeks.
The iris (my whole bed of irises actually) was just planted at the end of last summer, so this is their first season. Overall the plants all look great, I've got blooms or bloom stalks on 19 out of 21 of them including this one, so I don't think it's a soil deficiency, but then I haven't had the soil tested so... When I made the bed I mixed some native soil with top soil and garden soil. Fertilized when I planted and again this spring. I'm just hoping whatever it is doesn't spread to all the other plants!
Here is a pic of the whole plant in comparison to some of my others. It's the one closest.

Your Iris bed looks really nice..
But, as the queen of leaf spot, I'm going to disagree with the others.. Other than being unattractive, it doesn't seem to hurt the bloom or vigor of the plant. We had a relatively dry winter this year, and I have much less on the plants. The fungus is in the soil and splashes up on to the leaves. I've never been clear on whether it's already in the soil, or comes to the soil on infected plants. Solarizing the soil seems to help quite a bit the following year. Some varieties seem more susceptible than others. Some people spray, but I just live with it. I used to trim the leaves to (supposedly) slow the spread... but I have way too many Iris now, and didn't find that it made much difference here at fungus central anyway.
I've also had the streaky-spotting that is showing on your leaves. Some years ago, I brought a leaf into one of our meetings like yours (in a baggie) and Joe Ghio said it was leaf spot...
This is a semi- bad case on my 'Clotho's Web' last year.. but sadly not uncommon here.

with Sherry, it does look like leaf-spot. I leave it alone too unless I find a specific cultivar to be a leaf-spot magnet and then I remove the plant to reduce the contamination of the irises around it.

as well with Sherry, I have it some years worse then others, but I have never done anything about it. Wetter years it seems worse then dry ones. It usually shows up here about mid way through the bloom season. This year due to the very hard late frosts, I have many of the leaves twisting and turning in a wonky sort of way, some of the ends of the leaves have died back. Others have lost their terminal bud. Iris are generally tough. Sometimes, I think, we really do more damage then good by digging and prodding and constantly replanting an already weak rhizome.

Okay, well at least it's not terminal. So discouraging to have this happen the very first season 😞
We did have a period of continuous snow cover this winter (uncommon here), and a very wet Spring.
I think I'll just get rid of the main offender and hope for the best. But how long do I need to wait before planting something else in that spot, and should I treat the soil in any way?
@Henhouse, what did you mean by solarizing the soil?

Henhouse said:Your Iris bed looks really nice..
But, as the queen of leaf spot, I'm going to disagree with the others.. Other than being unattractive, it doesn't seem to hurt the bloom or vigor of the plant. We had a relatively dry winter this year, and I have much less on the plants. The fungus is in the soil and splashes up on to the leaves. I've never been clear on whether it's already in the soil, or comes to the soil on infected plants. Solarizing the soil seems to help quite a bit the following year. Some varieties seem more susceptible than others. Some people spray, but I just live with it. I used to trim the leaves to (supposedly) slow the spread... but I have way too many Iris now, and didn't find that it made much difference here at fungus central anyway.
I've also had the streaky-spotting that is showing on your leaves. Some years ago, I brought a leaf into one of our meetings like yours (in a baggie) and Joe Ghio said it was leaf spot...
This is a semi- bad case on my 'Clotho's Web' last year.. but sadly not uncommon here.

Sherry, are you the queen of leaf spot?

I get it in a bed where there are air circulation issues. (shrubs have gotten too big). Mine usually aren't harmed too much, but to me, it's indicative of too much moisture. And the issues are most prevalent in early spring. But sometimes I do get some pre-rot brown moistness in leaves. That's not aesthetic, that's got to be dealt with.

If iris beds are neglected, or aren't maintained enough, they're most likely to get leaf spot.

When I would help house-flip, there would be times I'd see neglected iris beds full of tall grass weeds etc. that would be severely browning and have leaf spot, terribly.

I naturalize my perennials, and sometimes during mid-late summer, if I don't keep up on cleaning-up (maintaining) my iris beds (removing the dead leaves, weeds, etc.) they end up looking something like this


So yeah, mine do occasionally get leaf spot, only if I don't maintain them enough.

I get a lot of leaf spot too.

Rick Tasco at Superstition solarizes his beds, and they are gorgeous.

You need to dig, and amend the beds you want to treat first. Make sure the soil is damp.. Cover with clear plastic in the summer for 4-6 weeks (i think that's what it was) and weight down.. I think I just put a little soil on the edges to seal it well. The heat kills fungus and weed seeds down several inches..

Here's a good article that explains it better than I can.
http://ipm.ucanr.edu/PMG/PESTN...

In my climate, I have to solarize much longer, as our heat isn't as intense as it is in Calif. I will cover the area with a Black tarp (get's hotter then with clear) in the spring and leave it for a year. Uncover it and plant the next year. Clear plastic here will act like a green house, and weeds will grow under it. I have done that more with my veggie garden then with iris gardens. I don't have trouble with tomato blight etc. then.

Henhouse said:Rick Tasco at Superstition solarizes his beds, and they are gorgeous.

You need to dig, and amend the beds you want to treat first. Make sure the soil is damp.. Cover with clear plastic in the summer for 4-6 weeks (i think that's what it was) and weight down.. I think I just put a little soil on the edges to seal it well. The heat kills fungus and weed seeds down several inches..

Here's a good article that explains it better than I can.
http://ipm.ucanr.edu/PMG/PESTN...

Sherry ~ Have you done this? I was just wondering if it is hot enough here to do that. It gets in the high 80's here. I want to solarize my smaller iris bed (rows).

Do you have cats roaming around? They sometimes spray to mark their territories.

evelyninthegarden said:

Sherry ~ Have you done this? I was just wondering if it is hot enough here to do that. It gets in the high 80's here. I want to solarize my smaller iris bed (rows).

Evelyn, I have, and it works really well.. No rot, very few weeds.. everything grew really well.

Sherry ~ Thank you so much! That will help me out quite a bit!