How to make tulips last a week
Tulips are the only cut flower that keeps growing after it is cut: up to two centimetres in the vase (sample note).
Cut the stems straight across, use a tall vase with a little cold water, and top it up every day. Turn the vase each morning so the stems do not all lean towards the window.
Keep them away from daffodils for the first day: daffodil sap makes tulips droop.