Boerner Botanical Gardens are botanical gardens located on the grounds of Whitnall Park in the village of Hales Corners, Milwaukee County, Wisconsin. The gardens are named for Alfred Boerner, who designed the original five formal gardens. The Annual, Perennial, Rock, Rose and Peony Gardens were constructed in the 1930s. Later additions included trial, herb, lily and shrub rose gardens, as well as the Bog Walk. Boerner Botanical Gardens is open from late April to early November, and closes for the winter.