Answer: Your success in keeping your new flowers protected during the freeze depends upon how long the freeze lasts. If it's just overnight, simply cover your vulnerable plants with old sheets or a product called "floating row cover". If it's an extended freeze simply covering them overnight may not work - you might want to mound insulating material over the entire plants. Use straw, leaf mulch, etc. and then rake it away after the threat of frost has passed.
Best wishes with your new plants!
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