The industry standard sedum species grown on vegetated roofs are very drought tolerant, and commonly do not require irrigation. However, Rooftop Green suggests installing an irrigation system as a safety measure for especially dry periods and for the establishment phase. 

If natural precipitation is less than half an inch for a 10-15 day period during the growing season, a watering session is vital in preventing plant dormancy or death. During these periods, approximately 1-2 inches of water once a week should be applied. 

All watering guidelines are general suggestions, and cannot take the particular weather conditions in your area into consideration. Please contact a Rooftop Green specialist if you have any questions. 

Yes. Invasive species will appear, even atop a roof. The keys to weeding are prevention and timing. Spot weeding should occur at least once a month to ensure weeds are removed before they flower and seed. Full weed sessions should occur in May and October, and often during the summer. 

No. Our species varieties are specifically chosen to be high coverage, yet low maintenance. 

The sedum mats installed in Rooftop Green modules take time to become established in their new climate. They should reach maturity after one full growing season--roughly a year.

Fertilization should occur during the Spring annually for the first 3 years after installation. A generic 10-10-10 slow-release fertilizer should be applied at the grass sewing rate.