You imagine that two foods called potatoes would be the same, wouldn’t you? However, in this case, a sweet potato is not a potato at all. They share some characteristics with each other, such as how they grow and what they contain, but they are not related in plant families at all. Both the potato and the sweet potato are tuberous foods that grow underground, they both originated in the same area of the world – that is, South America – and they both contain starches and other vitamins. That is where the similarities end.
The humble potato is related to, of all things, tomatoes, peppers, chilies, and eggplants. All of these belong to the Solanaceae, or deadly nightshade, family and, as the name suggests, all of the leaves and stems of these plants are poisonous. The potato’s botanical name is Solanum tuberosum. The plant is a small bush that needs to be started off every year with what is called a seed potato. You can grow your own potatoes at home from any potatoes, but getting hold of seed potatoes is the best way. The new plant grows from the eye of the potato. If you find a potato growing in your cupboard, you can plant it and you will get a few potatoes of the same variety. Potatoes are ready to collect after the plant has flowered and has died down.
Sweet potatoes are related to the flowering plants called Convolvulous and are in the family Convolvulaceae. They are a flowering vine and the sweet potatoes form the underground tuber. Their botanical name is Ipomoea batatas and, unlike potatoes, you are able to eat the leaves of these plants. The plant is classified as an herbaceous perennial vine with heart-shaped leaves and open trumpet-shaped flowers. Tubers are dug up while leaving the plant itself alone. It may die back slightly in cooler areas but will remain viable for several years. Its leaves and young shoots are eaten as a green vegetable. It is important to note that a sweet potato is not a yam. Yams are a different plant all together.