Just today, I ran across an article reporting about food crops in Russia.
It reports this about Russia's main staple food (starch/grain):
Russian households (inclusive of both urban and rural) collectively grow 92% of country's potatoes on their garden-plots, the size of which is typically 600 square meters [0.15 acres] for urban households, and typically no more than 2500 square meters [0.62 acres] for rural households
So see if the ideas put forth resonate with you, you are the only one who can know what is true for you.
They state that the Russian Monoculture system produces 43% of the Russian agricultural output on 83% of Russia's agricultural land. They also state that the Russian home gardeners produce 51% of the Russian agricultural output on 7% of Russia's agricultural land. I haven't been able to find any sources to actually back up these claims. I don't doubt that a polyculture system can produce more food than a monoculture system. It just seems the claims are overinflated.
Jonathan_Byron wrote:private gardeners...would hop on a train with two suitcases of tomatoes and sell them in Moscow on the black market, and they could make a few months salary per trip.