I actually mean square meter. If you can feed yourself on 50 m² of conventional gardening, fine, go ahead. Not my experience. Put up a blog, don't buy any food

I actually mean square meter. If you can feed yourself on 50 m² of conventional gardening, fine, go ahead. Not my experience. Put up a blog, don't buy any food anywhere else, post your body weight on a daily basis. But the OPs question was about balcony / window shelf gardening anyway. I don't think a lot of people living within cities have a >50 m² balcony.