The idea of green living is popular right now, and what better place to start than in the garden? Saving energy, reducing impact, and reusing materials are all part of going green. Ironically, one of the most intriguing places to put your new environmental awareness into practice may not be in the garden, but above it.

The idea of a living roof is not new. In Scandinavia, people have been building roofs with sod since the Middle Ages. And you’ve probably heard of the Hanging Gardens of Babylon? Of course, modern life and building practices bring new needs, and planted roofs continue to offer many benefits. Making a roof “green” extends the life of the roof, reduces water runoff and reduces energy costs (especially for cooling) up to 40%.

Plants absorb sunlight, whose energy would otherwise go into heating a roof’s surface. The evapo-transpiration of plant leaves also helps…