Mine are still fairly upright (South West), but are starting to shed leaves. If yours are starting to look tatty and green is appearing, if it's a sheltered garden you could do it. I heard rumours of a possible Beast from the East 2 in the next week or two, but nothing definite.
I'd wait till end of Jan just in case as the old stems will protect the crowns form damaging frosts. Keep an eye on it, just in case and then cut early Feb or whenever you spot the first new green shoots, whichever comes first and assuming it's not brass monkeys out there.
"We don't stop playing because we grow old; we grow old because we stop playing." - George Bernard Shaw
Thanks, I'll leave it a bit then. Please, please no more Beast's from the East @AnniD It only just started getting milder today, and I did my first gardening since the Autumn.
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