I don't do much besides compost and a bit of fertilizer.
So far we have put up 40 qts of tomato juice, frozen okra, 200 ears of corn, eaten all the asparagus, onions, cukes, squash, canteloupes, water melons, sweet and hot peppers, eggplant, broccoli, Brussel sprouts, beets, kohlrabi, spinach, etc and are awaiting the sweet potatoes to get ready. I have maybe $50 total invested and have given my neighbors at least a couple of hundred dollars worth of produce.
This is my other hobby and my summer savings for all the gas I will use this winter.