In 2016, Oakland community members created the Nishna Heritage Garden, located in the lot next to the Nishna Heritage Museum. The garden includes a large-scale mural that covers the museum's entire outer wall. The mural was created by Malvern artist Zack Jones and is titled "Time". The mural depicts scenes from the local area. The garden also includes picnic seating, native grasses, trees, flowers, and other public art pieces.

The mural was made possible by donations from local townspeople and grants from the Pottawattamie County Community Foundation, Farm Bureau, Pioneer Seed, and Iowa Arts Council.