In a bed in the garden I would divide pinks after flowering. These, grown in a container, do not look happy and I would suggest that they could divided as soon as you wish.

Thankyou Bulbaholic. I will do that straight away

I'd take cuttings from them as insurance, and also because they're short-lived plants.

Hi Spritzhenry, Thats why it looks a bit sad, its been there at least 5 or 6 years

I find that they rot at the base and get brittle. It's very easy to take cuttings, so go for it if it's a favourite plant. :-)

Ok thankyou Spritzhenry. i will take some cuttings