Located at the base of the 7 1/2 acre Mountainside Park, the Presby Memorial Iris Gardens contain over 14,000 irises of approximately 3,000 varieties and produce over 100,000 blooms over the course of the season. The annual spring Bloom Season is typically mid-May through the first week of June.  Visitors can see by the arching slope of the garden beds why Presby is often referred to as the “rainbow on the hill”.