Does anyone have a remedy for getting rid of sooty mold fungus and ash residue on rose foliage ?
It has been so hot and humid here, combined with airborne ash from fires, that my roses are covered in this messy stuff. The heat and humidity these past 6 weeks have made it unbearable to garden the way I'm used to and it got out of control.
I deadheaded all day yesterday and tried to spray off the mold with just water but with limited success...and they look abysmal.

I thought of using a diluted concoction of Dawn Dishwashing liquid soap since I used it once on an orange tree and it worked great. Citrus foliage has a way thicker cuticle and the spray didn't damage the foliage. Rose foliage is different, obviously, so I don't know if I want to risk using the same treatment or what proportions to use.

To further compound the issue, I have a lot of other plants in and around the roses that I don't want to damage if I use the Dawn and run the risk of ruining everything.

I do have both a tank sprayer as well as a hose end sprayer. I just don't know how strong of a solution to make.

Thanks for any input. Also, the mold is not from insects...the roses are completely insect free...no aphids, mealybugs, etc.

I'd worry about dish detergent in this heat. It might work, but it might really mess up the foliage. Maybe if you sprayed with that and then washed the daylights out of it with a garden hose. Maybe, repeat that a couple of days later?

We coastal folk, we're just not used to these temps (It was 107 deg here, day before yesterday) but I have an awful feeling we best get used to it.

Very good suggestion, Jeri.
Thanks.

I like Jeri's idea. Soot and ash are both greasy so you do need some kind of soap to cut that grease. Short of hand washing each leaf spraying is the best option. Make sure you spray the undersides to get all the mold spores too.