Arugula microgreens are young arugula plants that are harvested when they are a few inches tall. They are small, tender, and have a peppery flavor. 
 
Appearance: 
Delicate, green leaves with a heart shape and broad edges
Attached to a narrow, pale green stem
Smooth, pliable, and flat leaves
Flavor: 
Peppery, slightly buttery, and cabbage-like