Top yielding sweet potatoes Must grow Best potato to grow 100 days. Plants form well-shaped, uniform roots. Noted for dependably high yields and for lasting storage quality. Centennials could be the most widely recognized sweet potato. Carrot color inside with copper to orange outside skin. “Baby Bakers” in about 90 days. The Centennial has been used in many bake-off contests. Sweet potatoes grow best in well-drained, sandy loam soil with a pH of about 6.5. Using a small hand trowel, dig a hole about 4" or 5" deep and 3" wide. Place one slip in each hole with the roots pointing down. Position the slip so that the bottom half will be covered with dirt while the top half with all of the new leaves is above ground. Carefully fill the hole with dirt so that you don't bruise the new plant. Sweet potatoes don't like to be bruised or bumped around too much. When you have completely covered it with soil, gently press the plant and surrounding dirt to set the plant and to remove any remaining air pockets. Continue the same way until all of your slips are planted.