Answer:
A harvest sown and reaped on the same day in an unplowed field. Which increases without growing, remains whole though it is eaten within and without. Is useless and yet the staple of nations.
A warrior amongst the flowers, he bears a thrusting sword. He uses it whenever he must, to defend his golden hoard.
I'm white, I'm round, but not always around. Sometimes you see me, sometimes you don't.
A building where people and stories are on stage
What does everyone know how to open but not how to close?
Why was the cook arrested?