Potatoes are a popular vegetable on the dinner table and in the garden. Gardeners plant seed potatoes in the spring when the soil temperatures reach 50 degrees. Many types of seed potatoes are available for sale, including white, red and fingerling potatoes. Some potato varieties are best eaten within a few months after harvest while others can be stored for months. Sweet potatoes are another popular vegetable. These warm-season vegetables are planted as slips or plants in early summer, after all danger of frost has passed. While most sweet potato varieties have orange flesh, white-fleshed and purple-skinned varieties are also available. Sweet potatoes can be stored for several months and enjoyed during the winter months.