Thank you for helping me out. Now you have me stumped, as if the non-blooming squash are in the same soil, same sun, and same location then the only answer I can come up with is perhaps a mole or vole has damaged some of the roots of just the infertile plants. As for your second question, I think you should open the blossoms and try to hand pollinate them anyway. What have you got to lose? Write back and let us know if it works. Keep growing, Marianne Binetti