How do you plant food plants on your Home Street? It says there isn't anything to dig when I try, but I really want to plant some food plants in my backyard (on my Home Street).
There should be a "Cultivate" option near the top right of your game window. Click that and select a crop garden to place in an empty space. Just be aware that if you plant it on your home street, people who visit will be able to harvest from your garden as well, so place it in your backyard (once you enter your house) if you don't want other people to potentially take your crops.
Also, make sure you have the "croppery" in order to plant crops.