Why Use Sedum on a Green Roof?

Shallow Roots

• Sedum does not require deep soil to thrive. Planters can be as shallow as 4 inches deep, minimizing the weight and strain on the roof structure. Deeper and heavier would require costly new construction or reinforcing of many existing roofs. In addition, a sedum planter's low footprint will readily fit beneath the lip of most roof decks.

Drought Resistance

• Sedum is not dependent on frequent and heavy watering. The plant is a succulent, which means that it stores moisture in its stems, leaves and roots. This helps minimize weight-bearing requirements, which for sedum is approximately 17 to 18 lb. per square foot, depending on the specific variety of sedum used. At the same time, most species of sedum can endure periods of drought, so supplemental watering may be unnecessary after the roof is established.

Climate Flexible

• The 100 common species of sedum offer specific advantages for different climatic regions. A green roof in Chicago, for instance, might feature a sedum variety hardy enough for both harsh winters and steamy summers. A green roof in Phoenix might utilize a sedum species that thrives in bright sunlight and low humidity.

Low Maintenance

• Sedum plants spread out and form a rich, green, reflective ground cover that helps prevent heat buildup on the roof, which minimizes the maintenance needs of the roof itself. The sedum plants are also low maintenance and will not require major landscape management. Unlike grass, sedum will not need mowing or trimming. A low-cost moisture-sensing irrigation system will help keep the plants healthy at minimal expense.