Autumn care

Mrs39

Hi, I’ve had a new garden planted with some plants that I haven’t had before and I am a little unsure of which herbaceous perennials I can cut down to the ground in autumn such as sedums, agastache and campanulas. Any advice would be greatly appreciated 😀

Fairygirl

I only cut down perennials if stems have died right back, but any slightly borderline plants are best left with some top growth for protection over winter. Most Campanulas are fine in most parts of the UK, some Agastaches are less so. 
Salvias , for example, are best kept intact as much as possible unless you're in a mild part of the country   
I don't cut back Sedums - I presume you're meaning S. spectabile, which now has a new name - Hylotelephium?

philippasmith2

Not sure about some but I wouldn't cut my Sedums down until Spring.  They are in full flower now but even leaving them to die down naturally offers protection from winter cold and frosts.
They and the others you mention may look somewhat untidy when flowering is over and done with but otherwise, best left for the Spring clean up.
I'm sure others will have more informative advice so hang on for more replies