I think a good DIY organic pesticide is a glass/can of beer, equal amount water, a handful of chewing tobacco and some dishsoap. You mix the beer, water and tobacco and make a tea at room temp, strain it when ready and add the soap. Mix then store/add to spray bottle.
The little bastards don't like it and the spray will wash off come picking time.
I don't know if I would call a pesticide "organic" if it includes a handful of chewing tobacco. As someone who used to chew and knows what is in chewing tobacco, I certainly would not call it organic! There may be as many chemicals if not more in a can of chew than a bottle of pestide. But, I haven't chewed in years, so maybe they have chewing tobacco that is organic now since everything these days seems to be "organic"
don't know about chaw but you can get organic rolling tobacco that would work as well. It's pretty expensive but if you are trying hard. alternatly you could grow some tobacco you self and make your own. Actually tobacco makes a good companion plant for a lot of other plants to help discourage the bugs in the first place.
The other thing to try, depending on how much space you have, is crop rotation. If you plant the squash in the same place, or close to the same place every year the bugs know where to find it, if you can plant it some distance away from any place a susceptible crop has been grown in the last 4 years or so it can really help reduce pests.
When you are trying to reduce your spraying it's important to remember that 'organic' or 'sustainable' or 'natural' pest control is about control not elimination. You will still have bugs but you try to reduce the numbers while encouraging the plants to grow so fast they can stand up to the bugs. This is accomplished by slowely building your soil health and your little mini ecosystem so that you have balance and the predator/prey relationships in the soil, the air and on the plants are more in balance. Bat boxes can help control insects over time, raptor habitat can help control bird theft and rodent theft. Chickens or ducks can help control slugs and bugs as well as fertlizing the area in which they live and aerating the soil some.
There really isn't a good quick organic way to control bugs except maybe BT, pyrethrum (sp?) copper sulfate (this is actually for mildew I believe), and a few other 'approved' organic pesticides. I have had some luck with a soap, oil, garlic, pepper mix and adding some tobacco to that would help as well. also Diatomaceous Earth can be used to control ants which tend to encourage other unwanted creatures and should work against any hard bodied insect problem. But you have to reapply any time it gets wet. And make sure to get food grade DE as the other stuff (like for pool filters) is not good for your lungs or your pets.
DE can also be dusted on dogs and cats to control fleas, around the perimiter of your house to keep ants out, etc.