Answer: Sunflowers usually make great cut flower arrangements. Were your flowers in direct sun on your patio? Once cut, flowers can't handle being in sun, prefering dispersed light, preferably in a cool location. Here are a few pointers for cut flower preservation.
1. Harvest just before the flower peaks.
2. Harvest in the morning, if possible.
3. Use a sharp tool to make a clean, slanted cut.
4. Keep flowers in a cool area, but not in drafts.
5. Use a floral preservative, or make your own with 1 pint of regular 7-Up or Sprite (not diet) mixed with an equal volume of water with a teaspoon of household bleach, OR 1 quart of water with 2 tablespoons of fresh lemon or lime juice, 1 tablespoon of sugar and one tablespoon of household bleach.
6. Use warm water in the vase.
I hope this info helps!
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