Some of the best sweet potatoes I've ever grown, were in deep piles of hardwood leaves (not black walnut). The leaves keep down the weeds and grass and you don't want the clover coming through because
roots of any kind of plants, other than the sweet potatoes themselves will pierce right through the tubers and damage them. Just wait until the weather is really warm before planting them. I'm in N.C. too, and I usually plant, here in the mountain area, about mid to late May. I stick the roots down into the dirt and have about three inches of rotted leaves up around the plants, with the leaves of the sweet potatoes sticking out. Keeps them moist in dry weather too. If it rains a lot, may keep them too wet, so raised beds work good in those conditions.
Wild Edible & Medicinal Plant classes, & DVDs
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