Mary Jo Wegner Arboretum plans for next phase of growth

Multiple new additions were established and completed at the Mary Jo Wegner Arboretum in 2025 — and some big improvements are being planned.

The 155-acre, east-side arboretum is located at 1900 S. Perry Place on the north side of Highway 42 and marks the 20th anniversary of its dedication this year.

“By far, the most common response is: ‘I’ve never been out here before. I’ve driven by or come to an event and was amazed what it was like,'” executive director Mike Cooper said.

In 2025, “attendance was up, we had a large number of people who visited, and we had 68 rental events indoors and outdoors, which was one of our highest numbers. We had good response to field trips and summer camps, so overall visitation was up for rental activities as well as recreational activities.”

Visitors had several new additions to see, including the Tree Education Garden, where visitors can learn about tree anatomy and interact with a memory matcher to teach tree species and characteristics. New displays that will be installed will include how nature grows leaves and how nature grows trees.

The education garden was sponsored by the Bob and Rita Elmen Family Foundation, as well as the Woodland Trail, which connects the lower creek event lawn and “provides an interesting, winding walking path down to the prairie nature area,” Cooper said.

A new Memory Garden was initiated in the past year within the formal gardens, allowing another option for recognizing someone with a memory garden bed of perennial plants.

“We’ve had a good response to it,” Cooper said. “It’s another option in addition to sponsoring a bench or tree.”

The arboretum also added a hydrangea garden near the lower creek event lawn to honor its first executive director, Lori Kiesow. It was funded through private donations and honors Kiesow with a favorite flower.

“She’s out there every day and will serve on our executive board starting this year,” Cooper said.

The city of Sioux Falls made multiple improvements to the arboretum in 2025, including a new hiking area along the north creek area that flows into the Big Sioux River and the replacement of the Main Street bridge of East Sioux Falls. The 100-year-old bridge no longer was structurally sound and was replaced during the summer.

“It’s only used for pedestrian access and provides a much safer long-term connection to the trails in that area,” Cooper said.

The arboretum has been working through multiple updates identified in its 2020 master plan and now is set to tackle some of the larger ones.

The Mabel and Judy Jasper Education Center is scheduled to be expanded, with improvements to the historic classroom inside, more office space and a future connection to the planned Adventure & Learning Conservatory.

The expanded classroom planned at the education center

That project “is going to be designed more as a year-round place for kids to explore and learn about nature,” Cooper said “It’s not going to be like a playground but will be interactive and include some sculpture.”

The plan is to focus on fundraising for the next couple of years.

The education center remains an option for events this year, and a short distance away, the arboretum also is managing event bookings at the new Arrowhead House at Arrowhead Park, which offers a flex room and classroom, full kitchen, sitting room and fireplace plus a multilevel deck overlooking a quarry pond.

“We’re just starting to get activity out there,” Cooper said. “I think it could be more weekday smaller groups that want to use it, maybe graduation open houses and things like that. It has a beautiful view of the quarry ponds.”

The arboretum is open year-round, and despite the winter weather, there are still regulars, Cooper said.

“We have a lot of dog walkers,” he said. “They are grooming the trail for snowshoeing (when the weather allows), but people walk on their own or bring their dogs with them, which we encourage.”

The book “If Our Trees Could Talk,” released last year, has sold about 1,500 copies and is a fundraiser for the arboretum. It’s carried locally at Lewis Drug, Nyberg’s Ace Hardware, Crossroads Book & Music and Scheels, as well as at the arboretum’s store.

“The idea is that it will be an ongoing fundraiser, so it’s not a one-time printing,” Cooper said.