Sad looking sedum

[Mrs Pingu]

My sedum isn't looking very happy, any ideas what's wrong with it? Powdery mildew, something else?
2023-09-06_09-15-08 by The Pingus, on Flickr

[Flite]

Possibly just related to weird weather.
From your photo, it doesn't look too much like powdery mildew
But Sedums are very susceptible to vine weevil, esp when in pots.
Might be worth tipping it out and having a poke around the roots for juicy white grubs.

[Mrs Pingu]

The sedum bought last year and planted out got et by gastropods. This one I intended to leave in a pot for a few weeks before planting out, but never made it that far (cos I planted hunners of sunflowers instead). I was going to plant it when they've finished.
Possibly another plant to add to the list of I can't grow, along with all the lupins that I planted out 3 weeks ago (all demolished) and the wee echinaceas I planted out (also all demolished). Feckin snails.

[Flite]

Don't give up on sedums. They are usually pretty robust and brilliant for insects.
But in my experience they are not especially happy in pots, and this year the weather has made that worse.
In pots they have to be kept well watered, but that means the compost is wet all the time, especially if the pots sit in a saucer of water. Sun heats up plastic pots very quickly, so the roots are in hot wet anaerobic conditions- it cooks them!
Large terracotta (breathable) pots are better, as the water evaporates from the surface slowly, cooling the compost and letting air in.
Whatever, tip it out and look at the roots - post a photo?