The most common way to grow potatoes is to use "seed potatoes", sprouted potatoes saved from last year's crop or purchased from a reliable source. Since the tuber is not a fruit that results from pollination, this method creates plants that are genetically identical to the parent plant. (Clones!!!!) This gives you dependable results but there are some worries about depending on a relatively small selection of genetic material when potato diseases and pests are constantly evolving. For my first attempt anyway, I'm using seed potatoes.
I bought "Red Thumb" and "Nicola" from the Landreth booth the Boston Flower and Garden Show and I had a few leftover fingerling types from a local organic farm. I would avoid using any old potato from the grocery store - some are sprayed with chemicals or can harbor diseases that you don't want to introduce into your home garden. Many gardeners have a method for "chitting" or sprouting their seed potatoes that involves special temperatures and light requirements. I forgot mine in the basement and they sprouted just fine. I just wish I had taken them out of the mesh bag first.
I used the potatoes with the most vigorous, stocky sprouts. I cut a few of the larger potatoes in half, keeping a few sprouts on each piece. Cut potatoes should be allowed to dry at least over night so they can heal over a little before planting. I put mine in a paper egg carton because that seems to be what everyone else uses.
I want to grow fancy little fingerling potatoes, so I can space them closer than if you were hoping for big ones. I put 12 plants in a 6 x 3ft bed, which is still probably closer together than advisable. We'll see how it goes.
I dug two deep trenches and placed the seed potatoes sprouts side up. I only filled in the trenches half way when I covered them so that I have soil available for hilling in a few weeks. I'm also really trying to keep up with labelling things this year.