Fungus and Sweet Potatoes--- ick.

So each year I harvest my sweet potatoes and some of them have black skin..... some have gorgeous orange skin.  I am always back on the computer to figure out what it is... so once and for all, I am posting the reason here!  It is a fungus - but the fruit is FINE TO EAT!

What is wrong with my sweet potatoes? (http://www.richmondregister.com/lifestylescommunity/local_story_301073528.html)

Amanda Sears
Register Columnist

Several people have either called or come by the office about their sweet potatoes recently. Their concern was with the dark discoloration on the surface of the sweet potatoes. Is there reason for concern? The answer is no. What you are seeing is a condition known as scurf. Scurf is a soil-bourne fungus that colonizes the skin of the sweet potato, causing purplish-brown-to-black lesions. These discolored areas are merely cosmetic injuries and the sweet potatoes are fine to eat.

Scurf is transmitted from infected mother roots to transplants and then to the field. Once there, it can persist in the soil for years. This fungi only effects sweet potatoes and its plant relatives, such as morning glory. Rainy conditions can increase the severity of the problem.

As a producer, be sure to use disease-free plants when transplanting. Consider using vine cuttings instead of root slips. Do not use transplants grown from sweet potatoes that contain scurf. Also, choose a field that has not grown sweet potatoes in the last three years. Thoroughly clean equipment after working in infected soil. This is a good practice whenever dealing with any soil-borne fungus.

If transplants are suspected of having this fungal disease, you can cut off some of the bottom portion of the slip, which is the area which will contain the fungus. If you choose to disinfect your slips with bleach, be sure to use a very diluted solution, such as one cap of bleach per gallon of water, then rinse thoroughly with pure water. If the solution is more concentrated, it could prove harmful to the slips.

There are certain fungicides that can be used pre-plant. If you are interested, please call me at the Madison County Extension Office, 623-4072.

So, are sweet potatoes safe to eat if they have scurf? Yes. In fact, I would feel confident eating them myself … especially if they are in the form of a pie!