Mabery Gelvin Botanical Garden is an eight-acre public garden in Mahomet, Illinois, within Lake of the Woods Forest Preserve. Created through a $100,000 gift from H. I. Gelvin, founder of the Forest Preserve District, it was designed with help from University of Illinois students and named for his wife, Mabery, who died in 1971. Dedicated on June 30, 1974, the garden features waterfalls, a Japanese-style red bridge, a one-acre koi pond, and an All-America Selections Display Garden. It has remained active through major renovations completed in 2019 and a 2022 state grant supporting new plant production space and greenhouse upgrades.