A warm oasis: Milwaukee’s Domes recreate ecosystems from around the globe

Built in the 1960s, the Mitchell Park Horticultural Conservatory's round glass houses offer a respite from harsh Wisconsin winters

Entering the Desert Dome. | Photo: Julie Grace Immink

Growing up in the 1990s, I would plant myself in front of the TV and watch Totally Pauly every day after middle school. I watched all of Pauly Shore’s movies and even listed his alter ego “The Weasel” as my hero in the photo caption of my eighth-grade yearbook. (As an adult, I met Shore at The Comedy Store on Sunset Boulevard, and he signed that same yearbook.) So, when I first saw the Mitchell Park Horticultural Conservatory’s round glass houses in Milwaukee, Wisconsin—also known as The Domes—Shore’s 1996 cult classic Bio-Dome came immediately to mind. 

The curly-haired actor is best-known for irreverent comedies such as In the Army Now, Encino Man, and, of course, Bio-Dome. In the movie, friends Bud (Shore) and Doyle (Stephen Baldwin) accidentally get trapped inside of a biological experiment in the middle of the desert. The film is loosely based on real life: In 1991, scientists carried out two similar missions in the Arizona desert. The results of the first Biosphere 2 mission were mixed (and the second was even less successful), but today the site, located just outside of Tucson, is used by the University of Arizona and available for tours.

a glass half dome set against a snowy backdrop
The Domes in Milwaukee. | Photo: Julie Grace Immink

Eighteen hundred miles northeast of the Arizona desert, The Domes is a living museum comprising three glass half-spheres, each one recreating an ecosystem from different regions around the globe. Each dome sits on one acre of land, approximately the width of half a football field. They are the world’s only conoidal glass houses (others are geodesic). To design the structures, the Mitchell Park Horticultural Conservatory hosted a competition. Milwaukee architect Donald L. Grie’s space-age forms won, beating 33 other world-renowned architects. 

The first dome was completed in 1964 and the third was finished three years later. The million-dollar designs comprise 2,200 triangular panels made of quarter-inch thick glass embedded with wire. The all-glass ceilings are seven stories tall and allow natural sunlight to reach the landscape inside. Employees hand-water the interior plants daily. In 2008, the conservatory raised funds to improve the lobby and bathrooms; the restoration also included an LED lighting system installed between the glass panels, and the lights showcase the domes’ intricate architecture. At night, they glow in different colors.

Sausage trees

The Floral Show Dome features rotating, seasonally-themed exhibitions throughout the year, showcasing plants grown in greenhouses located on-site. During my visit, miniature evergreen trees, small topiaries, violas, and petunias in an array of vibrant shades are on display. The annual winter show, popular with families, features model trains that move throughout the floral arrangements. The Wisconsin Garden Railway Society installs the tracks and volunteers supply trains from their private collections. Modeled after the real coal-burning machines once ubiquitous throughout the U.S., the remote-controlled versions are built perfectly to scale. 

When I leave the colorful world of the Floral Show Dome behind and step into the Tropical Dome, I’m immediately transported into a steamy rainforest surrounded by more than 1,200 species of plants. I encounter trees that produce common foods such as cocoa, bananas, and coffee beans, and spices such as turmeric, cardamom, and peppercorn. More familiar plants such as ferns and philodendrons fill the winding jungle-like pathway. 

I’m particularly intrigued by a sausage tree. It’s named for its fruit, which resembles a string of sausage links dangling from the branches. The fruit casings can weigh up to 10 pounds and are poisonous to humans. Colorful orchids and a waterfall that flows into a koi pond add to the tranquil atmosphere. A wide variety of tropical birds, fish, and frogs help the ecosystem thrive. 

tall cacti stretch toward the top of a glass dome
Cacti trying to reach the glass ceiling in the Desert Dome. | Photo: Julie Grace Immink

Desert domes and exotic spices

Next, I explore a dry climate similar to those found in Africa and South America in the arid Desert Dome. Among the rocks and succulents on the sandy ground are living stones camouflaged throughout the pathway. Tall cacti pop up in this oasis, creating great backdrops for photographs. I examine different edible cactus types, hot peppers, and tuna fruit that thrive in the desert climate. Two agave types grow side by side; the plants’ core can be roasted and fermented to make mezcal or tequila. The flowering Euphorbias from Madagascar are the rarest plants in the conservatory’s collection. 

The Desert Dome is not only home to flora but some fauna as well, including Steve, a bearded dragon rescue. Since the conservatory doesn’t use pesticides on its plants, bugs and critters like Steve help eliminate harmful pests. 

In addition to the three domes, a wall-to-wall glass house called The Annex is billed as the only greenhouse in Milwaukee to double as an event venue. The 15,000-square-foot glass house  can be reserved for weddings and special events; the sunny room is also home to a winter market on Saturdays, where local farmers sell ready-to-grow mushroom kits, microgreens, small-batch cheeses, liquor-infused popcorn, goat-milk soaps, and various products from a local elk farm.

During the afternoon I spend exploring The Domes, I encounter nothing like the challenges faced by the researchers (or actors) locked inside of similar, highly controlled environments. In fact, the glass spheres are nothing but a welcoming, warm oasis—especially when winter temperatures in southern Wisconsin can hang around the single digits. The Domes’ connection to Bio-Dome may exist only in my head, fueled by pre-teen nostalgia—the actual movie was filmed at the Tillman Water Reclamation Plant in Van Nuys, California. But I do know that if I ever find myself trapped inside of The Domes, the first thing I’ll do is turn the agave into a tasty margarita. I think Shore—and Steve—would approve.

If you go

The Mitchell Park Domes are open Wednesday through Friday from 9 a.m. until 5 p.m., and on weekends and holidays from 9 a.m. until 4 p.m. Advanced ticket reservations are currently required and parking is free.