On Earth, human life is enabled by plants which provide us with calories, vitamins, fuel, medicines, and oxygen to breathe. In addition, recent scientific studies indicate that plant cultivation reduces anxiety and depression and has a positive influence on diabetes, heart disease, obesity, and longevity. It is likely that when humans travel to Mars they will continue this practice. The plants that Mars explorers take with them will provide a source of fresh fruits and vegetables , fresh air to breathe, and perhaps a psychological benefit that is crucial to the success of their mission.