I only plant 1 sweet potato plant it gives me 100 lbs of potatoes and I donate them all to the homeless shelter. You can buy or grow slips from a grocery store potato or cut the end of a potato off and plant it after it starts to grow slips=vines. I plant 1 plant in the center of a 60 foot row in full sun. Sweet potatoes love hot weather and they don't care if soil is poor. I make 1 vine grow in each direction from center in that row east/west or north/south. As it grows longer cover the vine with dirt every 3 feet to make it rot there. Let the plant grow until frost kills it. The mother plant will produce about 30 lbs of potatoes and all the satellite spots will grow about 8 to 10 lbs of potatoes. When frost kills the plant I dig them up. I usually get 100 to 125 lbs of potatoes my soil has lots of clay but I add peat moss to make it better. We get 190 days of rain every year in TN. June, July, August 105 degrees with very little rain. I sometimes give plants 15/15/15 fertilizer. June July Aug clay soil is hard as cement so I water at sun down to soften the soil. Be sure to keep grass and weeds out of the row. My rows are 32" apart for the tiller. I only plant 1 row of sweet potatoes along with 2 rows of tomatoes, 3 rows of beans, squash, 1 row of melons planted just like I do sweet potatoes, bell peppers and other things.