Traditionally home gardeners have planted potatoes in mounds of soil or in trenches, then hilled over with soil from the trenches. As the plants grow up they are covered with more soil. To avoid mounding the soil in advance, or digging a trench, or doing more digging, I have found potato production to be just as good using a mulch method.
I place the seed potato firmly in the top layer of soil and cover it with 4” to 6” of mulch. This can be grass clippings, old animal bedding, straw, leaves or compost. Anything to keep sunlight from the developing potatoes (so they don’t turn green), helps to retain moisture, keeps down weeds and helps support the plant.
I frequently use this mulch method, planting the seed potatoes 6 to 8 inches apart in all directions in 4’ X 8’ raised beds. This method is especially successful if using raised beds and you have clay or very wet soil .
On growing potatoes in mulch - Growing tip #1