I've been surveying my yard over the past couple weekends trying to catch up on some fall chores. One area that needed a little clean-up was a small rock garden bed located on the corner of my house. In that bed this summer I planted a couple ornamental sweet potato vines that did very well there. The frost killed them a few weeks ago so I decided to dig up the tubers. I was especially amazed at how big they had gotten this year.
I told you they were big!
Tubers are modifications of stems that swell up and store large amounts of carbohydrates - potatoes being the classic example. I dig these up not to eat, but to store and plant next spring. All that stored energy will help produce a much larger plant next year. You can eat these ornamental sweet potato's if you want, but I've heard they don't taste very well. Unlike the sweet potato grown in our vegetable garden, these oriental varieties are bred for their foliage, not flavor.
I store the tubers (as is) in paper bags, or wrapped in newspaper. I'll place then in a small uncovered box in my garage and forget about them until next spring when all danger of frost has pass. These vines do well in pots or planted directly in the ground in full or part sun. From my own experiences they do well in most soil types that drain well. I mix a little compost in the soil when I plant them and add a little mulch and then I'm done. When the first frost comes along in the fall these vines will quickly die back. Soon after that is when I dig up the potatoes. It's always best to dig them up before the ground freezes.
They are very easy to root from cuttings also: http://gardenhacker.blogspot.com/2007/11/rooting-sweet-potato-vine-cuttings.html