Blueberries are sweet, nutritious and wildly popular. They’re so tasty and convenient that many people consider them their favorite fruit. The small round berries can range in size from 5-16 millimeters in diameter. They first appear green, but ripen into a deep shade of dusty blue. The soft, hazy white coating that develops on the skins' surface, which is known as the bloom, is a natural waterproofing which helps protect the berries from the sun and other natural elements. Blueberries have a sweet and woodsy flavor with an acidity that can vary depending upon growing conditions.