“We want to make sure that you look at the soil, the vegetation, the hydrology, so that you are improving  or certainly not harming  the natural ecosystem,” he said.

Image American beautyberry. Credit... Darren Higgins for The New York Times

Deon Glaser, a landscape architect on the staff of the council who helped write the initiative, said that LEED has requirements concerning landscape, which address issues like reducing runoff from buildings and barring development within 100 feet of a wetland.

“But it doesn’t have specific requirements of how to do that,” Ms. Glaser said.

The initiative, on the other hand, goes into detail, specifying the kinds of plants, for example, that can be used to cleanse a disturbed wetland; how trees can be used to shade a building, protect it from wind, prevent erosion and clean the air; and what kind of plantings enhance mental health, draw people outside the building and even engage them in tending the landscape.

The Green Building Council “definitely wants to incorporate those aspects of green design and construction into LEED,” Ms. Glaser said. But that requires a long review process, she added, and a vote by the membership.

Still, Mr. Mims said, “we’re hoping that it will be incorporated into LEED in 2011.” (The Sustainable Sites Initiative can be downloaded at sustainablesites.org. Comments are being accepted until Jan. 20; then the guidelines will be revised and tested on pilot projects.)

IN its efforts to be more sustainable, the United States Botanic Garden now sends all its green waste to the Department of Agriculture’s composting facility in Beltsville, Md., or to Pogo Organics, a commercial composting system in Sunshine, Md. It also recycles paper, cardboard, bottles and cans, and sends plastic pots to a center in northern Maryland where they are cleaned, ground up and sold to a plastics manufacturer.