I think its a shade lover similar to a heuchera, with similar but less conspicuous flowers. It seeds itself but not enough to be a nuisance. I have some close together on a small but steep little bank, so it doesn't need mowing. Sorry can't remember its name.

It's Tellima grandiflora Tilly. Good in shade, it self seeds liberally, but not so much as to be a problem. I like it - it's quietly useful.

Thanks both of you. I didnt realise it would flower so an added bonus. It is beginning to swamp the 2 plants either side of it though, so i think i'll have to move it.