Winter squash fruits stunted

by Diane
(Cameron Park, CA)

I have several varieties of winter squash growing, butternut, acorn, delicata, and spaghetti. The plants are all doing well, except that 1) they are not producing secondary or tertiary vines, so I'm only getting 1 fruit on each vine, and 2) those fruit are very stunted, i.e. Acorn squash over a month along that is only fist sized, etc.

I am finding this really frustrating! I was hoping that with 15 plants, I'd have some squash to enjoy throughout the winter. The plants are in a raised no dig bed amended last winter with aged manure and compost, and regularly fed compost tea or fish/kelp emulsion. I'm in northern CA, where its been 80s or higher days since March, and they're in full sun. The bed is deeply mulched with straw. Help!