Q.My Dad Had No Male Flowers On The Squash Plants In His Greenhouse. He Paintbrush Pollinated Them With Flowers From The Cucumbers A
nd it seems the squash have set fruit. But they are two separate species and surely cannot cross pollinate?! None of the neighbour s are growing squash. Could it have actually worked? From looking it up it should be impossible for cucumber pollen to pollinate a squash plant. But every one of the flowers is female and every one has set, all painted with pollen from cucumber flowers. My dad is convinced he’s created something. I think it’s more likely a wandering bee or two just happened to be carrying pollen from a similar species and git into the greenhouse. What should we be expecting these fruits to be?!

Certified GKH Gardening Expert
It sounds like your squash was open pollinated by the squash next door. Many insects will wander from yard to yard looking for more squash pollen. Unfortunately, a hybrid between the two would not be possible. They are from different genera altogether and cannot cross. Had this been in the same genus, but different species, then this might have been a possibility.
Here are some articles on this search page that will offer more information on squash:
https://www.gardeningknowhow.com/search?searchTerm=%22squash%22