Potatoes can really be, let us say, interesting... Want to hear some interesting facts about them? Here you go. Potatoes are only 20% solid, in fact, they are 80% water! The average American eats about 124 pounds of potatoes per year while Germans eat about twice as much. To top off this, jungle of weirdness, in 1974, an Englishman named Eric Jenkins grew 370 pounds of potatoes from one plant! Just one.