Gardening helps you to feel calm and content. A study by researchers in the Netherlands found that gardening may reduce the stress hormone cortisol. In the study, the researchers gave two groups a difficult, stressful task. Afterward, to recover, one group gardened for 30 minutes, while the other group read indoors. Not only did the gardening group report better moods than the reading group, but they had measurably lower cortisol levels. (A reward after weeding in the garden - also another type of stress relief!)