Lavender
Smell it: Gardens don’t have to be all about edibles (even though you can eat lavender). According to the University of Maryland Medical Center, aromatherapy treatments involving lavender and a few other herbs are often used to supplement depression treatments, because the scent is so relaxing.
Grow it: Plant a lavender seedling in a container made from a material that breathes, such as terra-cotta, and choose a pot about 12 inches wide by 12 inches deep. Place your pot in an area that gets lots of sunlight; lavender loves dry, sunny areas. English lavender is both fragrant and edible, if you feel like adding some lavender flowers to your cooking.
More: Top 10 Flowering Herbs
Photo: Rodale Inc.