What is the "rule" for irrigating a green roof garden?

— baruch weiss Farmersville, OH

Answered by Richard Heller on July 5, 2010

Green roof to offset the required land space for zoning?

— feng schaefer

Answered by Kathy Spence on February 2, 2010

Are there any cost-cutting shortcuts for planting a green roof on my urban townhouse?

— Rachel Diamond, Harrisburg, PA

Answered by Mark Schrieber on August 25, 2009

What's the difference between a green roof and a white roof?

— Angela Corcoran, Brooklyn, NY

Answered by Susan Wisniewski on May 2, 2008