Growing a glossy-leafed sweet potato vine indoors is a time honored project for children and an inexpensive way for adults to create a decorative house plant. Growing sweet potatoes indoors won't produce a crop of yams for you to bake, but it will result in an attractive vine that can can frame an entire kitchen window. This planting project is simple enough for school children to successfully complete it, and only takes minutes a day for maintenance to keep it looking fresh and growing longer.
Shop for sweet potatoes that have already begun to sprout. Many commercial growers spray sweet potatoes to prevent sprouting in the store, but sometimes the spray isn't effective and you will find one that has sprouted. If your store has an organic produce section, you will probably find sprouted sweet potatoes there.
Push toothpicks into the center of the potato, so that they stick out to hold the potato up suspended over the water in the jar. If you don't have toothpicks handy, use skewers or plastic forks to hold the sweet potato.
Place the sweet potato over the opening of the jar so that the pointed end is facing down and about half of the potato is in the jar. The other half will be held up by the toothpicks. Fill the jar with water, leaving about 1 inch of room empty at the top.
Place the jar in a sunny window. Top off the water every day to replace any that evaporates. In about a week you should see small hairy roots coming out of the bottom of the sweet potato. Red sprouts will come out of the top of the sweet potato about one week after the small roots arrive. These sprouts will quickly turn green and start growing into vines.