Answer: It sounds like your plants are not being pollinated. Pollination is required to set fruit. Check to see if bees, the top pollinators for cucumbers and 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 cucumber or squash behind the bloom) with an artist's paint brush. 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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