Sweet potatoes are at the bottom of the list of gardeners' favorite vegetables, and that's just not right. Varieties such as 'Beauregard', 'Vardaman', and 'Centennial' are truly exceptional (much better tasting than the kind in the store). Kids love to watch sweetpotatoes grow. And the slips (that's what the cuttings are called) are almost impossible to keep from sprouting as a recent study in Georgia demonstrates.
Melvin Hall, a sweet-potato breeder at the Coastal Plain Experiment Station in Tifton, has been growing sweets all his life. He recently experimented with the cuttings to see how much it mattered if you put them in the rooting medium upside down or the right way up. He found out it doesn't matter one bit. They all rooted just fine and didn't waste any time doing it.
"This is something I had heard from growers for years that's backward from everything you learn about plants in school," Hall said. "I thought surely it had to slow the plant down a little if it's in upside down. But the sweetpotato is practically a weed, and all the slips rooted very readily."
Sweet potato cuttings make roots in about two days, without rooting hormones, when the temperature is warm. If you just throw them on the ground, most will root if the weather is warm and the earth is moist, Hall adds.
If your frost-free season is at least 90 days, you can grow good sweetpotatoes. The old-fashioned way is to start slips by sprouting a tuber in a glass of water. But the process is too slow and the tubers available in the store aren't the best, according to Hall. It's better to buy slips through the mail. They may look a bit tatty when they arrive, but just set them (roots down) in loose, warm earth -- and then get out of the way!
Article published on June 23, 2008.