High Quality Content by WIKIPEDIA articles! Presby Memorial Iris Gardens (6.5 acres) is a nonprofit, volunteer-run living museum specializing in iris flowers, located at 474 Upper Mountain Avenue, Montclair in Essex County, New Jersey. Following financial problems in 2008 and 2009, ownership of the gardens was transferred to Essex county, who bought the Walther house for 1.1 million dollars in order to give the Iris gardens a better financial standing. The county then leased the gardens back to the Presby Memorial Iris Gardens for $1.