“I thought it was about time someone did something for the ol’ town. So many take so much from Dubuque but leave so little behind.” – Jackson “Mac” Marshall
In 1975, Jackson “Mac” Marshall set out to leave Dubuque a lasting gift—51 acres of land: 36 acres of open meadow and 15 acres of walnut timber. But Mac had three conditions. The land had to remain a park forever, he could stay in the farmhouse whenever he wanted, and the city had to begin developing it within a year.
His generous donation planted the seeds for something extraordinary. By 1976, two big ideas took root. Jim Schwarz and the Tri-State Garden Club dreamed of a botanical garden, while Frank Hardie envisioned an arboretum. Their shared passion sparked a movement, rallying a team of dedicated volunteers who rolled up their sleeves and got to work—planting, planning, and transforming the land into a community treasure.
The Dubuque Parks Department approved leasing 16 acres of Marshall Park to seven determined Tri-State Garden Club members: Jim Schwarz, Gene Heinemann, Mel Gottschalk, Ambrose Hoeger, Marlyn Bausman, Jack Frick, and Frank Hardie. Each chipped in $20, grabbed their shovels, and started planting trees, bushes, and flowers. They built fences and arbors and even hauled water in gallon jugs—whatever it took to bring their vision to life.
Back then, the land held only two structures: Mac’s farmhouse and an old hay barn with a lean-to cowshed. Local nurseries and gardens generously donated roses, peonies, and hostas, while volunteers shaped the landscape. As renovations on the barn began, even more people joined the cause, helping turn a dream into reality. That very barn would later become the Heinemann Visitor Center.
By 1982, the Arboretum had taken root—literally. A well was drilled, and the first eight raised garden beds were installed. That same year, the Jodi Bausman Memorial Garden was created, showcasing prairie grasses, wildflowers, and heirloom roses. On July 4, 1982, the Arboretum hosted its first fundraising event, drawing 100 cars full of visitors eager to witness the transformation.
Membership blossomed to 144, and leadership expanded. Gene Heinemann became president, Ted Kopper was elected first vice president, and Dave LaRue stepped in as second vice president. With Jim Schwarz leading growing operations, a greenhouse was added to the visitor center. The Arboretum had officially become a thriving hub for gardeners, nature lovers, and volunteers alike.
Over the years, the Arboretum flourished. It earned recognition as an All-American Rose Selections Public Display Garden. Music in the Gardens, a free summer concert series, became a beloved tradition. A wedding gazebo, shade structures, and memorial gardens—including a Veterans Memorial—were added. The first Tri-State Lawn & Garden Expo was held, and the Japanese Garden, designed by world-renowned landscape architect Hoichi Kurisu, marked its 30th anniversary in 2024.
A Lasting Legacy
Fast forward to 2025—at its 45-year milestone, the Arboretum now welcomes 85,000 visitors annually. Supported by four full-time staff, one part-time staff member, and nearly 300 volunteers, it continues to grow. New gardens, educational programs, community events, and accessibility improvements keep Mac Marshall’s vision alive.
From a handful of passionate gardeners to a flourishing botanical treasure, the Dubuque Arboretum & Botanical Gardens stands as a testament to the power of community, proving that a simple idea, nurtured with dedication, can grow into something truly spectacular.
