I have read an article that a family of 4 can subsist on a farm of 1 hectare that would be a mix of orchard and vegetable farm plus animals. The article is a sort of prescription for rural folks to convert 1 hectare of their land for their food needs. The garden cum orchard can be tended by 1 person. So that means a family of 4 can still till their big farm for their usual farming and the 1 hectare would involve only the patriarch. The model has 5,000 square meters for a variety of vegetables particularly sweet potato and crops like corn. 3,000 square meters is reserved for trees of their choice that would include banana and papaya. The remaining 2,000 square meters is reserved for their housing and animal husbandry of at least 4 female goats or 2 female cattle plus 10 hens - all animals with corresponding male counterparts for reproduction.
I've heard that in some parts of the world as long as someone owns two or three cows, that will provide milk all year round, assuming only one of the cows will be dry, the milk produced can be enough to provide the family with everything they need and the proceeds will also buy the cows food. And all this can be done on land that is less than 1/8 of an acre. So yeah, 1 hectare is big enough land for self-sufficient farming.
In reality you really need 1hectare per person to be sustainable long term! Anything much smaller and you need to import energy!
While a hectare may seem to be overkill concerning the amount of land needed to feed a family of four, one must take into account the need for crop rotation to keep the soil nutrient-rich as well as extremes in weather (heat, cold, drought, floods) and crop loss due to insects and animals. I have been gardening for many years and if I get an 80% crop yield, then I am quite pleased and will have plenty of food for myself and my family.
