Here in the UK, allotments are currently back in fashion - garden-sized strips of land assigned to people who rent them for a small amount each year. Currently in demand again, especially in cities where flat-dwellers might not have their own garden - you can spend a few hours a week getting out of the house and getting some exercise / fresh air. A traditional allotment does take a bit of a time commitment, and of course not every day is sunny, and free allotments in some areas are very limited, so maybe combine allotments with a farming robot. Get a parcel of land, maybe a way outside town (but accessible via public transport), split it up into allotments that people can farm daily remotely or come and visit for a nice day out. The sort of thing a farm with a farm shop or pick-your-own operation could diversify into - rent out strips of land for remote users to tinker around on, handle shipping them their ripe produce for a reasonable fee.
