I have two thoughts. You might have squash vine borers. Check to see if the base of your plant is mushy. If it is, you have squash vine borers.To get rid of them, you need to inject BT into the stems (??? I've never had them, but others have had a lot of trouble with them.)

My other thought was that your insect control worked too well and has killed off or kept the bees away. No bees, no pollination, no fruit. If you use the pest control, you'll need to hand pollinate the squash.

I'll look for the squash vine borers -- what's BT?

There are plenty of bees around, but I don't think pollination is the problem as I keep looking (that is, every morning) for female blossoms (so that I can hand pollinate them) and there just aren't any.

Thanks!!

Fertilizing it every 10 days may be puting more growth into the leaves and not into producing flowers.

OTOH, My yellow squash is not producing any female flowers, and it isn't getting the Miracle Grow treatment. For me the zucchini is producing (we just ate three last night), but have only one 2-inch yellow squash on the vine. We had a very cool spring, and have had nights in the 50s all along (well, we usually only have a couple of weeks of nights in the 60s, but that is usually when the squash really takes off).

BT is a bacteria that causes a toxin in caterpillars' stomaches, killing them.

Catherine (yes, zone 5, but on a cool mountain side)

ygofast, BT is Bacillus thuringiensis. Below is a wicki description of it.

Greg
Nevada

Here is a link that might be useful: BT