Lettuce

This leafy green is a popular choice for regrowing because it has a shallow root system and requires minimal space. To regrow lettuce, cut off the bottom inch of a lettuce head and place it in a shallow dish of water. Within a few days, new leaves will start to grow. Lettuce is often used in salads and sandwiches, but can also be used to add texture and flavor to wraps, tacos, and burgers.