Gardening Articles: Edibles :: Vegetables
All About Sweet Potatoes (page 3 of 3)
by Jim Wilson
Which Sweetpotato Should You Plant?
I know that memory plays tricks, but I remember that sweetpotatoes tasted better when I was a boy in Mississippi. I checked with Dr. T. P. Hernandez, a Louisiana sweetpotato breeder who retired a dozen years ago. He, too, recalls the extremely sweet, soft-fleshed, moist, reddish purple sweetpotatoes that were sold as "Louisiana Yams." They were the cultivar called Unit One Porto Rican, but commercial growers in Louisiana had to stop growing them because of their susceptibility to a number of plant diseases, Fusarium wilt in particular. I am willing to concede that perhaps more of the starches in Porto Rican converted to sugars in baking, but I can't split a baked sweetpotato today without a pang of nostalgia for the good old days, yam scam notwithstanding. Dry, yellow sweetpotatoes make me long for the true Porto Rican roots.
Most of the newer varieties are vining types. 'Beauregard'(early, free of strings even if stressed and resistant to soil rot) and 'Jewel' (good flavor, resistant to stem rot and internal cork diseases, preferred for sandy soils where seasons are long) account for 90% of commercial plantings.
It's a different story for home gardeners where bush types make better use of limited space. Two popular bush types are 'Vardaman' and 'Bush Porto Rico'. Some seed catalogs list these as maturing in 100 and 110 days respectively. They can do it in a warm summer, but in zone 5 they need floating row covers to concentrate heat and to hustle them along early and late in the season (temperatures can rise too high during midsummer for row covers to remain over plants).
Dr. Melvin T. Hall, a sweetpotato breeder at the University of Georgia's Coastal Plain Experiment Station in Tifton, confirms that 'Georgia Jet' (aka 'Jet'), a soft-fleshed vining type, is ready for harvest in 90 days or less from Georgia to New York. 'Centennial', a blocky orange-fleshed variety with copper skin, also matures in 90 days. Sumor is a white-fleshed 90-day variety. Many of the colorful heirloom varieties, such as 'Bermuda Pink', 'Kore Purple', 'Frazier White' and others are only available through the Seed Savers Exchange, a network of seed-saving gardeners based in Decorah, Iowa.
Now if by some misfortune you live in California or Arizona, you have a problem. Out-of-state mail-order nurseries cannot ship sweetpotato slips to you. It's the best excuse to start your own slips from market sweetpotatoes sprouted at home. The only nursery I know in the West that grows and ships sweetpotato slips is Exotica Rare Fruit Nursery, P.O. Box 160, Vista, CA 92085 (catalog, $2).