Hello. I`m a newbie here but want to give you a bit of advice about covering your flowers. The best way to prevent heat stress and protect your flowers from the direct sunlight is a shade cloth or row cover. Just make sure your garden can still breathe and grow. If you cover plants too closely, helpful insects such as bees won’t be able to work their magic and heat will get trapped and defeat the purpose of shading in the first place. Choose the cover really carefully. You can visit makeitcovered.com to create your own check-list and choose the best covers for your garden. Talking about me, I recently bought a lawn mower and had to choose a cover for it. This site has helped me. Maybe it will help you. Good luck with finding the best cover.