I have a question for some of you who might know. What do you do to remove sooty mold stains on your hosta leaves? Apparently my huge hickory tree gets aphids every year. I am only guessing because my backyard gets a fine coating of sticky coating on everything after the tree already finished flowering. Plus there are lady bug larvae crawling underneath. Hostas are bug free. They are not photo worthy now but I will post some later.
I am going to try washing with 1T soap to 1 gallon of water to start.
Some of it peals off but some won't rub off.

I have never had to deal with that , hope it works.

Never had this issue, found this info:

https://gardenerspath.com/how-...

I get that in my shade beds in the front of the house. They're shaded by hickory trees only. I used to hose the plant off and rub off with fingers. I don't think it hurts the plants. It just makes them look dirty.

Rose, my plants are under a giant hickory. The hosta near the oak and maples don't get it.
RJ, thanks for the link. There is no way for me to go after whatever insect is producing the honeydew as I am convinced it is many stories above me in the hickory canopy.
I did do a tablespoon of Dawn in a bucket of water and wiped with Mr Clean's Magic Eraser, then a rinse. The results are good so far. I may have rubbed off the blue but new leaves are still coming in. I just have to go over those with puckering. Maybe a toothbrush for that. Time will tell if the Magic Eraser is too abrasive.

This occurs a bit later in Canada. How did you find the Magic Eraser long term? I wouldn't have thought of trying that, but might.

I thought I posted a follow up on that. I don't recommend it as the leaves scorched soon after.

I take the lazy approach…. I just ignore it! I always tell people to come see my gardens before the end of June. After that they start looking pretty tired.

I still don't know for sure what makes everything sticky every year. Maybe there is something I can spray ahead of time that will prevent it from forming but I doubt I will follow through on that.

The overhead trees have aphids which drop a sticky honeydew which then gets mouldy. I get it mostly on the hostas under my Linden tree. And mostly I ignore it. Yes, I invite people to come up to the middle of July. Just yesterday someone contacted me and wondered if I'd like to take part in a neighbourhood garden tour at the end of August. Uh, no! We had such an early spring that lots of my hostas think it's the end of August already. And with the amount of rain we've had, the slug damage is much worse than usual.

That is what I think it is.