Sweet potatoes should be harvested no later than the first fall freeze because cold temperatures can damage the sensitive roots. However, you may want to harvest earlier if you prefer a smaller sweet potato. Test dig a hill to see if they are the size you want.
Sweet potatoes should be cured after being dug. The digging process often damages the tender skin, and curing helps these small wounds heal. Place the roots in a warm, humid location for 5 to 10 days immediately after digging. A location with a temperature around 85 to 90 degrees is ideal. A space heater can be used to heat a small room or other area. Raise the humidity by placing moist towels in the room. The curing process not only heals wounds but also helps convert starches to sugars. This process improves the texture and flavor of the roots.
Sweet potatoes should be stored above 55 degrees. Storage at temperatures below that injures the roots, shortens storage life and gives them an off flavor. (Ward Upham)
