aaah writes
Thanks for the excellent advice. Unfortunately we had to buy the
items in a hurry and the previous owners have now disappeared. I
think what has confused matters is that this must be the hardy
variety, whereas I have also had some of the showy non-hardy variety
which have now died back... thanks again.

Why do you say it must be the hardy variety?

What are referred to as hardy geraniums are in the genus Geranium, the
wild UK members of which are known as Cranesbill. They typically have
blue or pale pink flowers, of darker pink (but never bright shocking
pink) or white. They are usually grown in the ground - they are not so
showy as specimen plants so aren't usually grown singly in pots.

What are also colloquially known as geranium, but aren't, are in the
genus Pelargonium. They tend to have much brighter flowers, red, or
bright pinks. Never blue. And their leaves are thicker and stiffer than
Geranium leaves. With the mild autumn we have had, there is no reason
why they shouldn't still be in flower. I have one which has been
flowering continuously for four years (in a pot in the porch).
--
Kay