Outdoor veggie and fruit gardeners, how do you protect your crops against disease and from becoming a buffet for pests and wildlife?

I'm growing tomatoes, peppers, and cucumbers for my first time not on a balcony, and I'm a tad concerned about caterpillars, squirrels, and other wildlife finding their way to my crops; that said, I would like to keep my space as earth friendly as possible, so chemical pesticides are out. I've read blog articles about [trimming the lowest branches to prevent disease](https://www.almanac.com/how-prune-tomato-plants-bigger-harvests) and [planting trap crops such as nasturtiums and marigolds to lure pests away from the tomatoes](https://www.almanac.com/how-use-trap-crops-deter-pests). Do these techniques actually work? How do other gardeners handle this situation?