But labour costs and capital costs are very high. It's not a really profitable operation. Labour of love really.
Most organic market garden type places are only a couple acres.
2.5 of premium wine grapes with on-site winery could also be profitable except around here and in most places regulations explicitly forbid wineries that have acreage that small. Around here it's a 5 acre minimum and then most townships have much more stringent regulations on top of that yet.
In general anything "value added" (jams, wines, bread, butchered/prepared meat, whatever) can be used to turn a a pure small "farm" into a more profitable operation. But again, costs.
(I have a 6 acre property, with about a 3/4 acre of grapes for my own use).
My dream is to have a farm with enough crops to cover my food & maybe sell a little extra. Out of interest does anyone know a good place in Europe where that's possible for a good price?
IMO making a profit would be the hard part - the internal market is small and in general produce prices are low.
Look at machine farmed fields just before harvest; the fully grown plants will often be quite close together.