The greenhouse at the United States Antarctic Program's McMurdo Station holds perhaps the most important patch of vegetation on the continent. To anyone not living there, it probably wouldn't be all that impressive -- just 200 square meters of plants, fruits and vegetables, including lettuce, tomatoes and pansies [source: SpaceRef]. However, when you're living in the harshest environment on the planet, a roomful of plants and vegetables is an amazing thing, especially considering they all have to grow without any soil or access to natural light.
Because of the continent's prolonged periods of darkness and light, the McMurdo greenhouse forgoes a traditional glass ceiling. Instead, it resides in a warehouse that uses artificial light to replicate normal day and night cycles. To prevent any microbes from contaminating the Antarctic environment, all plants have to be grown hydroponically (without soil). Despite the limitations this harsh environment imposes, the McMurdo greenhouse is extremely successful. It can produce more than 300 pounds of food per month, including as many as 750 heads of lettuce, allowing the people stationed there to have a fresh salad several times a week -- a real luxury in Antarctica [source: SpaceRef].