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
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
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
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
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
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
“So much of our life has been helped by the cultures of the
rainforest,” she said. “It’s really something we shouldn’t
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.”