You can replant them. It's about making the most of the space. Really what you're aiming for is never having any empty space. As soon as something is whipped out, shove something else in!
Just make sure you add plenty of rotted manure or compost (where appropriate) and organic fertilisers.
and of course, don't plant the same family in the same space. Ie - no overwintering leeks after your onions.
I'm putting leeks in after the spuds and brassicas after the garlic.