Answer: I don't know whether or not your boxwoods will come back. I'd give them the benefit of the doubt, though and continue to water them on a regular basis. With any luck, you'll see new growth soon.
For year around color in the bed with your caladiums, you might want to plant both annuals and perennials. Here are the top 10 Annuals for your growing region:
And, the top 10 Perennials:
American Alum Root
Best wishes with your garden!
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