[prawn]

I can't see how you'd have a chance. Isn't that 3x6 metres?! Literally everything would have to be perfectly efficient and go right without weather incidents, pests, etc. And I think you'd still need to supplement it, or have some miserly meals.

[LaserToy]

I did some math. Assuming a human male needs around 3000 KCal per day, it sums up to around 1,095,000 KCal per year. Potato is one of the most calory dense, as 1 acre produces 17.8 M KCal (found online).

So, one person will need 1 Acre (43560 sq feet) / (17.8 / 1.095) = 2679.6741573 sq feet of potatoes. Which will be 248.8872 sq meters (10 by 20 meters field).

It is either my math is wrong, or article is wron by order of magnitude