Organic vs. Conventional Sweet Potatoes
By Will Wollett
The sweet potato is a warm-season, spreading vegetable of tropical origin. It is a good choice for a home garden or a bigger farmer because it is easy to grow, is drought- / heat-tolerant, and has few pests or diseases. The sweet potato is also very nutritious, low in calories, and can be found in local markets year-round although they are in season in November-December.
Since 1971, North Carolina has ranked as the No. 1 sweet potato producing state in the U.S. It’s hot, moist climate and rich, fertile soil are ideal for cultivating sweet potatoes, averaging at nearly 50% of the U.S. supply. Where I live I am surrounded by N.C.’s top sweet potato producing counties, Wilson, Johnston, Edgecombe and Nash which help account for about half of the state’s supply. Another fact about the sweet potato I bet you didn't know is North Carolina designated the sweet potato as the official State vegetable in 1995.
Every fall once we have finished harvesting the potatoes we plant a cover crop in all our fields. We do this because with our farm being organic the cover crop acts as our nitrogen source for the next season. We plant Rye and Vetch as our cover crop. We do this so that the Vetch will climb the Rye stem which makes the vetch grow faster and easier. As shown in the picture above, disking the cover crops is our first step in preparing the soil.
Once the cover crops are disked in, we will bed the soil into rows, we do everything with a 2 row bedder, setter, and plow.
Sweet potato sprouts are planted 9 to 10 inches apart in the center of the ridge row and at a depth of 3 inches with at least 2 plant nodes underground and 2 or more leaves above ground. The sprouts are watered well immediately after transplanting
Cultivate as many times as you can with a rolling cultivator. You can not spray anything on the crops that are organic, so cultivation is important for weed control. With conventional potatoes, you can plow 2-3 times a season to apply fertilizer and to control emerged weeds. Cultivator gangs are set to throw dirt on the sides of the ridge . After sweet potato vines have grown down the sides of the ridge you can turn the tines up so that you can still plow the middle of the row. If the runners are cut from the plant it's not a big deal. It will shock the plant and will make it grow at a faster rate to replace the cut vines.
This is the plow that all of your big farmers use. It is a simple two row plow that turns the row over and lays the potatoes on top of the soil. It is fast but it does cut a lot of the potatoes up if not deep enough in the ground, but if you go to deep you will then cover the potatoes up. This year we found a potato digger that is two row. There are two chains that will carry the potato up out of the soil and then lay it back down on the ground.
Sweet potato roots are harvested 90-120 days after transplanting or immediately after a frost has blackened the tops of the plants. Sweet potatoes are very susceptible to damage at harvest; therefore, hand-harvest is preferred over mechanical harvesting.
The trucks drive through the field beside the workers. The workers hand the buckets to a man on the truck who empties them into a 4 bushel box. Once they are loaded as this one is, they head to the buyer.