You grow sweet potatoes in a different way than regular potatoes and at a different time of year.
Growing Sweet Potatoes
Sweet potatoes, also called yams in the United States, are related to the morning glory. They, like the Irish potato, came from Peru and Ecuador originally. Sweet potatoes are part of the root of the plant and each plant has between 4 and 10 eating size potatoes.
Although Southerners often call sweet potatoes yams, they are two separate vegetables. Sweet potatoes are grown commercially in the United States There are many commercial farms in East Texas that grow sweet potatoes each year. Yams grow in the Caribbean.
Sweet potatoes are started from slips, much like onions. These slips are planted when the danger of frost is past, around April 15 for North Central Texas. Plant the slips 4-5 inches deep, covering several of the nodes on it. Space the slips 8-14 inches apart and leave 38-42 inches between rows.
You need to fertilize with a balanced fertilizer such as a 10-10-10. Apply half before you plant and work it into the soil, then apply the other half in a side dressing 3-4 weeks after planting. Do not put any fertilizer down within 60-80 days of harvest.
Sweet potatoes require a lot of water, especially when the slips are trying to get established. You should, however, stop irrigating 2-3 weeks before harvesting. The proper time to harvest is when foliage starts yellowing.
The sweet potato will ruin if it is left out in the sun after harvest. However, it needs to sit out in an area that is 85 degrees or so for about 7-10 days right after harvest to cure. After that, it can be packed in straw or newspaper and will keep 3-6 months. Freezing ruins the raw sweet potato, but it may be frozen after it is cooked.
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