Help over feeding

[Soberfutures]

Hi all
Novice gardener here but usually muddle thru.

Have roses and azelea that usually I don't give any extra type of feed just sometimes baby bio basic. My DH bought a feed and did it himself so I've no idea if quantity was correct or even method lol. He seems to say put it about the plant and watered them....... not they look shit. I'm assuming too much of the feed had tipped a balance of PH or nitrates etc.

Will post pics of the plants and the box of feed.

Do I just water to try and wash it out??? Also a pic of my azela that he doesn't have appeared to have ruined.

Also the box and my good azalea

Flush them through with water so that it drains away, the. Leave them to dry. I don’t think iron will harm the azalea.

Flush it through with water - gallons and gallons of it.

Thank you. I figured it was water and more water. Just wanted to be sure. It say it was for Roses azaleas and rhododendron. Obviously he just used way too much. Fingers crossed. And thank you

With the rose do I cut them back as the leaves on my bigger one do look dead? Or or very limp. Will this correct itself with the water or should I prune it?