I have some in a raised bed and they are withering away or already dead. What do I do with them now? Do I dead head them or just leave them? Their green stalks are still there, do I cut these? I'm a bit clueless!
let them wither and go brown - it means that the sugars in the leaves get to the bulbs for next year (someone will have a far better technical explanation for what happens) and don't cut them until they're brown and crispy. Tie them up with string if you want to put something else in the bed. Are you going to lift them or leave for next year?