Even on the coldest of winter days, there has for the past 20 years been a perfect place in Madison to stay toasty warm. Not only does this place maintain a year-round temperature of at least 65 degrees, it offers a tropical feel, with high humidity, lavish green plants and colorful blooms around every turn.
This lush locale is the Bolz Conservatory, Olbrich Botanical Gardens’ greenhouse gem, and it is marking its 20th anniversary this coming weekend with a number of special events.
The celebration is well deserved, said Olbrich director Roberta Sladky, given how much the conservatory has meant to the community since it opened on Nov. 1, 1991.
“We have showcased the rainforest in programming and education,” she said. “It has given us the opportunity to bring more of the world culture into our public gardens.”
When the conservatory opened, Sladky added, “Olbrich became a year-round destination.”
John Wirth, conservatory curator, was in on the project from the beginning. As soon as Bolz was built — at a cost of $4.6 million — he was hired from Felly’s Greenhouse and assigned the task of filling the conservatory’s 10,000 square feet of space.
“It was a chance of a lifetime,” said Wirth, 59, who majored in horticulture at UW-Madison. “Obviously, if I’m still here 20 years later, I really do love my job.”
And there’s nothing more rewarding, he said, than seeing people enjoy the environment, especially in colder months. “I love seeing people just sitting in here in January on the benches, just soaking up the humidity and the warmth.”
Wirth’s work in acquiring the conservatory’s plants two decades ago began with walks around the empty space. He checked how the lighting looked at different times of day to help determine what plants should go where, knowing that different plants had different light requirements, taller plants would shade shorter ones, and so on.
Wirth made a long list of plants he’d like to have at Bolz. With the help of a plant broker, he visited various nurseries in the Homestead, Fla., area that dealt in subtropical and tropical plants, and found what he needed. Plants were trucked back to Madison for planting at Bolz, which has about 24 inches of soil atop 12 feet of sand.
It’s worth noting, Wirth said, that a year later, in August 1992, Homestead took a direct hit from Category 5 Hurricane Andrew, essentially wiping out every nursery where he had shopped. But about 80 percent of his original plants from Homestead are still at Bolz today. The largest plant at the time, a palm specimen about 10 or 12 feet tall, now rises more than 30 feet toward the top of the 50-foot dome.
In all, more than 650 plants grow at Bolz, representing more than 80 plant families and 475 species. More than 2 million people have visited Bolz in the past 20 years, and Wirth said he is rewarded on occasion when he meets guests from a tropical climate who compliment the conservatory.
“I’ve met people who grew up in India or the tropics,” he said. “They see plants they had in their yard.”
An Olbrich greenhouse not open to the public is used to grow many flowering plants that are brought in for display at Bolz when they bloom. Among these are the poinsettias used in Olbrich’s “Holiday Express” flower and train show and rare orchids Wirth has collected on several trips to Central America and South America. The blooming orchids have their own display area along the conservatory’s upper walkway.
Along with the many plant varieties, Bolz has several species of tropical birds and a small pond with koi, Japanese fish.
“The challenge now is maintenance,” Wirth said. “People talk about ‘green thumb,’ but a lot of it is just observation.”
And dedication. Wirth and two other full-time conservatory employees make sure that someone is on hand every day of the year. Wirth himself spends most days working three to four hours in the morning before Bolz opens to the public.
Fertilization must be carefully monitored to “keep plants looking green but not overwhelm the space,” he said. On a daily basis, the conservatory requires watering, cleanup of plant debris (volunteers offer invaluable help with this, Wirth noted) and light pruning. In addition, the conservatory is closed for two weeks every April for more major pruning, Wirth said.
“We have to let more light in up top,” he said. Also, he noted that creating more space with pruning is important for one of the conservatory’s most popular annual events, “Blooming Butterflies,” which runs in summer months.
“The open areas really help with the butterfly event,” he said.
The “Blooming Butterflies” program is one of many ways Olbrich connects with the Madison-area community through the conservatory, Olbrich director Sladky said. There also are numerous special exhibits and educational programs for all ages throughout the year that emphasize the importance of the world’s tropical rainforests.
“So much of our life has been helped by the cultures of the rainforest,” she said. “It’s really something we shouldn’t forget.”
Sladky said the existence of the Bolz Conservatory, a joint effort of the city and the Olbrich Botanical Society, “really shows the commitment of both the city and the philanthropic community.” Seventy-five percent of the original cost was paid for with private donations, including a lead gift from the family of Adolph and Eugenie Mayer Bolz, and 25 percent by the city.
“It’s a little less common to have a conservatory of this quality in a community the size of Madison,” she said.
And how great, Sladky added, particularly in winter, that Olbrich visitors can “experience a little slice of the rainforest right here in Madison.”