Iris has leaf spot

Question: I am cutting the tops as it is ugly.  Is there an OTC fungicide I  can apply? Should I apply compost?

responder: Jacki D., Master Gardener Diagnostician Volunteer (Washington, Multnomah and Clackamas Counties) Oregon State University Extension Service Volunteer Metro Master Gardeners (http://metromastergardeners.org/) Replied April 22, 2024, 7:30 PM EDT
response: What kinda of Iris? When does it bloom?

responder: The Question Asker Replied April 22, 2024, 9:01 PM EDT
response: It is evergreen Iris Foetedissimo.  The soft purple flowers bloom in late spring, then red berries appear.On Mon, Apr 22, 2024, 4:30 PM Ask Extension <<personal data hidden>> wrote:

responder: Jacki D., Master Gardener Diagnostician Volunteer (Washington, Multnomah and Clackamas Counties) Oregon State University Extension Service Volunteer Metro Master Gardeners (http://metromastergardeners.org/) Replied April 23, 2024, 1:31 PM EDT
response: I’ve grown this Iris also, and found the fungal leaf problems an issue many years. Sanitation for Iris is important, and these evergreen type seem to always have some fading foliage to infect new leaves. Cutting all foliage right before new leaves emerge is one strategy. Keeping the plants spread out for airflow and foliage as dry as possible is common advice. Fungicide can help protect emerging leaves, but can’t cure leaves once infected.  I found some resources with more details: this from Iowa State Extension and then from WSU also. Follow labels for use with any materials you apply. Exact options may vary by state.

responder: The Question Asker Replied April 23, 2024, 4:31 PM EDT
response: Thank you so much for the info! Good and sad to hear you have had this problem. We've had no problems for 20 years,  so we've been lucky.I may try digging them up.  Are there certain plants I shouldn't plant in their place, as I doubt I can get rid of all of the leaf spot.Thanks  Cheryl On Tue, Apr 23, 2024, 10:31 AM Ask Extension <<personal data hidden>> wrote:

responder: Jacki D., Master Gardener Diagnostician Volunteer (Washington, Multnomah and Clackamas Counties) Oregon State University Extension Service Volunteer Metro Master Gardeners (http://metromastergardeners.org/) Replied April 23, 2024, 4:59 PM EDT
response: It appears the fungus lives in foliage, not on the soil, and infects Iris, so replanting something else is fine after you’ve cleaned up well. Twenty years was a long time to only now have it show up. Is there maybe more shade than before?

responder: The Question Asker Replied April 23, 2024, 7:25 PM EDT
response: Actually, there were grape vines there, but they are gone, for our dogs' health.  Our scottie enjoyed them!  Now there is American wisteria there, but it doesn't cover the iris. I think the area is less shady now. ??? See photo attached. It is the north side of our house.On Tue, Apr 23, 2024, 1:59 PM Ask Extension <<personal data hidden>> wrote:

responder: Jacki D., Master Gardener Diagnostician Volunteer (Washington, Multnomah and Clackamas Counties) Oregon State University Extension Service Volunteer Metro Master Gardeners (http://metromastergardeners.org/) Replied April 23, 2024, 11:19 PM EDT
response: It does look sunny. The Missouri Botanical Garden lists it as good for a shade garden. I wonder if it will adjust to the current light conditions and the fungal issues will decline? If it were my garden and I wanted to keep the Iris, I would thin out the crowns (tubers) and aggressively reduce the foliage. If the new foliage got heavily infected again, I would probably choose a new plant for this location. I wish you success in with your garden, however you proceed.

responder: The Question Asker Replied April 23, 2024, 11:31 PM EDT
response: Thank you!  I appreciate your advice!On Tue, Apr 23, 2024, 8:19 PM Ask Extension <<personal data hidden>> wrote: