US No. 1 (3/4 inch min). Potatoes goodness unearthed. Full of vitamins and minerals. Tips and Trivia: Potatoes were the first vegetable grown in space. Cut potatoes can be stored in cold water for up to two hours to prevent discoloration. French fries were introduced to the United States by President Thomas Jefferson in 1801, at the White House. Health Benefits: Fat free. One medium potato provides 45% of the daily value of vitamin C. Cholesterol free. Excellent source of potassium. Produce of USA.