Answer: The phlox is rather short and would bloomfor a short time far earlier than the impatiens. The phlox also requires full sun. Along with a shorter form of impatiens you might have luck with the annual ageratum which blooms all summer and is a bit more flexible about the amount of sun it receives. If you need a perennial, you might try Veronica "Goodness Grows" if the spot is in a good bit of sun.
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