I have a big compost/manure pile I leave in place to slowly decompose. Last year in it I had volunteer squash, pumpkin, tomatoes, fruit trees, sunflowers, etc, sprouting, apparently from seed from kitchen waste. Kind of made me wonder if I'm working too hard at this. Maybe make the whole garden a compost pile and dump seed into it and see what happens. Kind of sounds fun to see what surprises I'd get.