I've "grown" squash in past years, in that I've transplanted seedlings or started my own. Many years they got off to very promising starts, but rarely did we harvest more than a couple of zucchini and a spaghetti squash or two.
This year I started seeds of:
6 Green zucchini (seedy Sunday) - 3 survived transplanting
8 Romanesco zucchini (seedy Sunday, and new to me) - 3 survived transplanting
3 Spaghetti squash seeds (that I saved) - all survived
3 Pumpkin seeds (saved) - 1 survived transplanting
3 sugar pumpkin seeds (saved) - 2 survived transplanting
2 kabocha squash from saved seeds.
I gave each of these plants about 4 square feet of space, and also gave them trellis structures to climb if they chose.
One of the problems I've had in the past has been powdery mildew killing my squash, presumably from the leaves getting wet during watering or from rain. Despite 2019 being a very rainy summer, that didn't happen this year, and all of these plants thrived and grew to be enormous. I suspect the beds being in full sun all day helped a lot with preventing the mildew and with the overall growth.
The spaghetti squash took to climbing the trellises, over the edges of the planters and out across the lawn. They shared 24 square feet with the three zucchini, two rows of carrots, and the cucumbers I attempted to grow, and out competed all of them in both amount of foliage and amount of fruit produced - zucchini included. Note for next year - isolate the spaghetti squash!
The green zucchini really seemed to be a fail, until I was taking most of the foliage down and found one huge zucchini from each plant hidden under everything. They'd put all their effort into those lost fruits!
The green zucchini that did grow was eaten as zucchini chips (dehydrated or baked) and some shredded and frozen for use in baking.
I also learned that squash will cross pollinate, and ended up with some funny looking spaghetti squash this summer.
The pumpkins were a very pleasant surprise. This is the first time I've succeeded in growing pumpkins, and ended up with 5 or 6 vine ripened orange pumpkins (that were turned into jack o lanterns) and 4 sugar pumpkins. The sugar pumpkins are being turned into cheese cake and other sweet fillings. It takes a lot - A LOT - of plant to produce a pumpkin, and I think I'll have a dedicated pumpkin patch next year tucked into some corner.
The kobacha produced about 8 fruit. I'll try them again, hoping that a warmer growing season allows the fruits to be larger.
By far the best squash from 2019 was the romanesco zucchini. I haven't had it before but it's really great for cooking fresh. Unlike other zucchini it's not all watery and tasteless, and stays firm when cooked. It's great curried. The three plants produced very well, and when I grow it again this summer I'll be mindful to pick it when smaller, to encourage even more fruit. Most of the Romanesco was eaten fresh, and some was cubed and frozen. Not sure it will keep it's firmness though.