Onions are a vegetable that comes in many popular and delicious varieties. Red onion, white onion, Vidalias, scallions, shallots — each species has its own distinct taste yet is just as flavorful as the next. Oniongardening.com, a website dedicated to homegrown onions, mentions that their price and accessibility are just two of the qualities that make onions so popular. Onions should be grown in a well-weeded area, and they thrive in the presence of other vegetables, like peas and turnips.