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Sweet Potatoes

Sweet Potatoes

Sweet Potatoes

This tropical root crop is started from small plants called slips or vine cuttings. Slips are produced by sprouting sweet potato roots in moist sand or sawdust. Cover roots in a box or bed with 3 to 4 inches of sand or sawdust, water, and keep warm (80 °F). In a few weeks when sprouts are several inches long, pull them from the roots. Additional slips develop and can be used for later planting.

Before planting sweet potato slips (homegrown or purchased), cut about 1 inch from the base of the stem to reduce disease problems. Use starter solution when setting slips in the garden.

Vine cuttings are slips cut at the bed surface with no roots or cuttings taken from the ends of slips set in the garden earlier. They have the advantage over slips of further reducing disease and insect problems. Vine cuttings several inches long can be made until July 1. These cuttings root rapidly when set in warm, moist soil.

Sweet potatoes need warm soils and about 90 to 110 days from setting the plants until harvest. Even good roots will produce poor yields if the soil is clay, wet, or overfertilized with nitrogen. A good sweet potato fertilizer has a ratio of 1-2-4. Select a loose, well-drained soil that allows for root growth and easy digging. Side-dress 3 to 4 weeks after transplanting with a low nitrogen, high potash fertilizer. Many sweet potato varieties flower in late summer. Sweet potato flowers are similar to morningglory.

Dig sweet potatoes when the soil is fairly dry and the air is warm. Early harvest results in many small roots. Late harvest results in jumbo roots and possible cold injury. Do not let freshly dug potatoes sit in the sun; they scald easily. If exposed to temperatures below 50 °F, potatoes may develop hard spots in the roots, a condition known as hardcore, or be chilled and begin to break down.

Problems in growing sweet potatoes are sweet potato weevil in the southern half of the state, larvae of various insects that burrow into the roots, and the diseases scurf (soil stain) and soil rot. Clip the base of the slips before planting or use vine cuttings to reduce scurf infection. Acid soils help to control soil rot. Cracks in the roots indicate nematode damage or interrupted growth caused by periods of drought.

Varieties

  • Beauregard—light rose skin; moderately deep orange flesh; high yielding; some disease resistance but not resistant to nematodes.
  • Centennial—variably tapered to cylindrical root shape; medium to large size; orange skin; deep orange flesh; vines thick and vigorous.
  • Jewel—blocky shape; smooth copper skin with rose blush; orange flesh.
  • Unit I Porto Rico—old variety; no field disease resistance; root shape variable; copper skin; yellow-orange flesh.
  • Nancy Hall—popular old variety with no disease resistance; light orange flesh.
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Publications

Publication Number: P1782
Publication Number: P1091
Publication Number: P2364
Publication Number: P3076

News

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Filed Under: Greenhouse Tomatoes, Vegetable Gardens June 10, 2021

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Filed Under: Lawn and Garden, Flower Gardens, Plant Diseases, Vegetable Gardens May 26, 2021

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Filed Under: Flower Gardens, Vegetable Gardens May 10, 2021

With the summer season fast approaching, I’ve been getting questions about fertilizing, primarily concerning the types of fertilizer and how much to use.I’m glad to get these questions because garden and landscape plants need fertilizer to keep them healthy and growing. Fertilizing at planting helps trees, shrubs and flowering plants get established. It also promotes shoot and root growth, flowering, and optimum fruit and vegetable harvest.

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The month of May signals that it’s time for me to start planting culinary peppers in my home garden.

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Filed Under: Lawn and Garden, Flower Gardens, Plant Diseases, Trees, Vegetable Gardens April 29, 2021

As warmer weather creeps in, many people find themselves spending more time outdoors and working in their yards. If you’re like me, you’ve probably made a trip or two to your local garden center looking for plants and other garden necessities. After reading over May’s garden checklist, it looks like you may need to make a few more trips. Here are some tasks to check off this month. 

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