The LEED-NC v2.2 requirements is for no more than 12 months. According to a LEED Reference Guide addendum from 7/19/2010, the time period was been increased from 12 months to 18 months for LEED 2009 projects, but USGBC has not altered the timeframe for pre-2009 projects.
Question
How long can a temporary irrigation system for plants to be established remain on site and have the project still be able to achieve the credit?
Credits