Tweva I did not know about the fungus, thanks. I really like the idea of being able to leave something dormant underground for next season. The fact that the plants kind of look like some of the weeds that grow around here makes it very attractive as a hidden food source.
MB, The “seed” for potatoes grows under the ground instead of above ground like normal plants do. If you keep covering the sprouts up the plant thinks it has not broken the surface yet and puts out more roots from the stem. The more roots you have the more “branches” you have to grow potatoes on. It would take a lot of dirt and work to cover a field of potatoes. When you have that many plants and that much room it is just easier to plant in rows and harvest what one layer of dirt produces.