Seem to remember someone saying "if only it was edible, I'd never starve"
it is edible though - the young tender leaves are.
cook like any other greens it says. not tried it
i dug up a big patch last year and was well pleased to find not much has emerged since. i pull up what i can when something does poke through, at some point the plant will have exhausted itself if it cant photosynthesize.