I apologize about the pond picture before… I’ve attached the actual pictures this time. My sedum leaves are turning yellow and red and falling off, did I over water them, or did they get too much sun? I live in Minneapolis, MN zone 4, the pants are 2 years old and this is the second year they've done this. I did cut them completely back in the Spring.
Oh, those don't look happy at all. These plants shouldn't give you any trouble at all in your zone. They're tough and reliable, and seeing them look like this is a bit puzzling.
First of all, I have no idea if they're overwatered - you will know better how often they're getting any irrigation. One thing I would question is the soil type. If they're in clay soil, or you have some kind of organic mulch, this could be the culprit.
Sedum hate moisture retentive soil or mulch. If you possibly can, start adding gravel or lava rock to the soil, and gradually start lifting them up so that they're above the soil - I would wait for the fall to do this, if it's hot where you are, this could be the death of them.
They can take full sun, so I doubt if that's the problem.
I would also cut them back. Sadly, although the flowers are desirable for the fall garden, it's very stressful for the plant. This might boost them into a new growth spurt, with some healthier foliage. What have you go to lose, right?
Hope this helps,
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