Answer: Squash plants produce both male and female flowers. Male flowers are the first to show up, followed by female flowers. You can tell the difference: male flowers have a thin, straight stem; female flowers have a slight swelling immediately behind the petals. Only female flowers will produce fruit, and that's only if they are pollinated by flying insects such as bees and wasps. Insecticidal soap should not affect pollinating insects, but they may be avoiding the area because you've been spraying your plants for whiteflies. Try this - wait until dusk to spray Insecticidal Soap. Whiteflies and aphids will be on the plants, but bees and wasps will be safe in their nests. By the next morning, the odor of the spray will be gone and the pollinators may come and visit.
Hope this helps!
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