Difficult to say - if they're not hardy, you just dead-head and enjoy them while they're in flower. Same with hardy ones, but you can plant them in the garden, but don't cut them back - the top growth helps to protect the plant and you should see new shoots appearing in the spring.

I have a non-hardy plant and i've just potted it into a large pot with violas round it. It'll last until the first frosts.

Have you got space to plant them out in case they are hardy?

Sorry - that's not a lot of help.

Mine were bought late form the garden centre and repotted a couple of weeks ago, and they are looking as healthy as ever, with ever more flowers appearing.

I buy large ones each year here in the Czech Republic. £1 a pot!

I repot them into bigger pots, deadhead as far as possible (I leave usually before they have finished flowering) and hope to see them again the following year. It's a bit hit and miss, some of them make it, some don't. One year I dug all of them into the ground and they all died so now I just leave them in the pots, not even wrapping them up.

This year I bought a dozen small ones as well and have been potting them on as they grew. I shall be interested to see how many make it through the winter (temps here regularly drop into the minus teens.....)