Answer: Lack of early fruit set on squash is most likely due to lack of male or female blooms or lack of pollinator insect activity.
I suspect you are seeing male blooms and the female blooms have yet to appear. Often when squash begins to bloom, it produces only male blossoms. There may be 3 to 4 male blossoms opening for several days to a week before the first female blossoms open.
If you have both male and female blooms, the problem may be lack of pollination. Check to see if bees, the top pollinators for squash, are out there working the blooms. If not, you can take over the task by transferring pollen from the male blossoms (attached to the vine by a thin stalk) to the female blossoms (they have a miniature squash behind the bloom) with a Q-tip or an artist's paintbrush. This must be done daily for best results.
Be extra careful about insecticide use around your plants. Insecticides can kill bees when used on blooming plants. If you kill the bees, you get their job!
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