Close-up of iris (Tennessee state flower) at University of Tennessee Botanical Gardens in Knoxville. Photo by aaron gilson on Flickr (noncommercial use permitted with attribution / no derivative works).
Official State Botanical Garden of Tennessee
Tennessee designated the University of Tennessee Botanical Gardens in Knoxville as the official state botanical garden in 2013. The botanical garden is part of the UT Institute of Agriculture (with botanical gardens located in Knoxville, Jackson and Crossville). All State Plants & Gardens
Quote from UT Botanical Gardens website: "Some 4,000 annuals, perennials, herbs, tropical plants, trees, shrubs, vegetables and ornamental grasses are evaluated each year. Both the Knoxville and Jackson gardens are TN Certified Arboreta. The gardens are open during all seasons and are free to the public."