It looks like this question double-posted, so I'm sharing sfmiller's answer here to keep responses all on the same thread:
"You can harvest squash blossoms as soon as the flowers start appearing. But if you want squash fruits as well as blossoms, you need to leave at least some female blossoms on the vine. Female blossoms have a fleshy ovary behind the flower, where it attaches to the vine; it becomes a squash if the flower is pollinated. Male blossoms attach directly to the vine and have a more hairy or downy appearance (and different reproductive parts inside the flower, if you look closely)."
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"You can harvest squash blossoms as soon as the flowers start appearing. But if you want squash fruits as well as blossoms, you need to leave at least some female blossoms on the vine. Female blossoms have a fleshy ovary behind the flower, where it attaches to the vine; it becomes a squash if the flower is pollinated. Male blossoms attach directly to the vine and have a more hairy or downy appearance (and different reproductive parts inside the flower, if you look closely)."