Not sure what you mean 'prune'. But all I do is to remove the dead leaves and old flower stalks about now.

Yes me too Owdboggy. Did it today so now got healthy green leaves only. Looks much better.

We have one called K. northiae which has huge leaves, like 3 foot long and 6 inches wide at the plant. They are evergreen so removing them is not really an option. However they do get very tatty, so with them I take a pair of scissors and cut the ends off in the same shape as they should be. Haircuts for Red hot pokers!

i've done that before too :o)