Domes Fun Facts

Aerial view of the Domes

Did you ever wonder how thousands of plant species could be protected from insects and parasites in the domes with no pesticides? As a child did you count every pane of glass in the domes? If so, do you remember how many there are? Did you know the Mitchell Park Domes were introduced to the world by a famous first lady? Check out a few of the interesting facts about the Mitchell Park Domes.

The Domes were designed by Donald L. Grieb, a Milwaukee architect, who won the design competition out of 30 architects in 1959.

Construction took several years with each dome staggered. The Show Dome was completed in December 1964, the Tropical Dome in February 1966 and the Desert Dome in October 1967. First Lady Mrs. Lyndon B. (Lady Bird) Johnson dedicated the facility to the people of Wisconsin in 1965.

About 250,000 visitors from over 100 different countries visit the Domes, including 10,000 students in formal programming and another 10,000 students informally.

There are five full time horticulturists, as well as an interpretive educator and support staff who care for the Conservatory collection, outdoor gardens and green roof.

The "Gifts Under Glass" Gift Shop is operated by Friends of the Domes to generate funding for educational programming.

Friends of the Mitchell Park DomesMilwaukee County Parks

Tech Specs

  • 1.

    Size

    1 acre under glass; each dome is 140 feet across by 85 feet high (7 stories); 750,000 cubic feet.

  • 2.

    Shape

    The world's only conoidal (not geodesic) glass house; the unique shape allows a better angle for solar heating and more height for tall trees.

  • 3.

    Structure

    Concrete frame with aluminum guttering and glass skin.

  • 4.

    Glass

    2,200 triangular panes of 1/4" thick wire-embedded glass is in each Dome.

  • 5.

    Heating

    Four one-million BTU low-pressure boilers fueled with natural gas, with a fuel oil backup system, heat the complex.

  • 6.

    Cooling

    A fan system around the base and at the top of each dome keeps them cool. A complete air exchange is done in 3-1/2 minutes.

  • 7.

    Getting To The Top

    A maintenance elevator is suspended inside the top of each dome and can be lowered to within a few feet of the floor.

  • 8.

    Pest Control

    No pesticides are used on the plant material. Beneficial insects and toads eliminate harmful pests.

  • 9.

    Watering

    The plants are watered by hand every day. City water is pumped in to a water tank and then heated. The Tropical Dome also makes use of an extensive misting system.

  • 10.

    Wildlife

    Eight species of tropical birds, frogs, fish and lizards live in the Tropical Dome. Beneficial insects and toads live in all three domes.

  • 11.

    Tallest Tree

    The Kapok Tree, Ceiba pentandra, can grow 200 feet tall and up to 10 feet in diameter. Because the Tropical Dome is only 85 feet, 20-25 feet must be removed each year by Parks Forestry.

  • 12.

    Rarest Collection

    The Madagascar collection in the Desert Dome.

Tech Photos

Architect Donald Grieb
Domes Construction
Mitchell Park Domes under Construction
Mitchell Domes under Construction
Domes under Construction
Lady Bird Dedication in 1965
The Domes Elevator
Kapok Tree
Kapok Tree Fruit