A Growing Concern

The New York Botanical Garden may well be the most verdant and changing National Historic Landmark you’ve never seen

The New York Botanical Garden is an elixir for the soul—a 250-acre eden founded in 1891 and thriving today just 20 minutes northeast of Midtown Manhattan. I spent much of my life riding past this paradise on commuter trains, never stopping to see the 50 diverse gardens and plant collections within its boundaries.

But after my first visit four years ago, I haven't been able to stay away. I've now admired the sculptures inside the landmark Enid A. Haupt Conservatory. I've explored the annual orchid show in spring. And last year, I learned about two jewels in the garden's crown: the recently renovated Peggy Rockefeller Rose Garden, and the newly restored Stone Mill, "one of New York City's most picturesque remaining pre-Civil War industrial buildings," according to the garden's president and chief executive officer, Gregory Long. 

Standing on the banks of the Bronx River, which runs through the eastern part of the botanical garden, the Stone Mill was built in 1840 by the P. Lorillard Company for its bourgeoning tobacco and snuff business. Having established tobacco fields in Connecticut and offices in Manhattan, the company moved industrial operations to the Bronx at the turn of the 19th century.

The water-powered mill functioned until about 1870, when the tobacco company opened a huge manufacturing plant across the Hudson River in New Jersey, and the obsolete stone structure was abandoned. Twenty years later, in April of 1891, the surrounding land became part of the botanical garden when the New York State legislature set aside acreage in the Bronx for "the collection and culture of plants, flowers, shrubs and trees, the advancement of botanical science and knowledge … and for the entertainment, recreation and instruction of the people." The garden officially acquired the mill in 1937.

If You Go ... 

The New York Botanical Garden is open year-round, Tuesday through Sunday, 10 a.m. to 6 p.m., with the exception of Jan. 11-Mar. 4, when it closes at 5 p.m. The Peggy Rockefeller Rose Garden has a five-month season, typically beginning in late May and lasting through October. The garden is easily reached via MTA Metro-North Railroad and New York City Transit. For more information, call 718.817.8700 or go to nybg.org.    

In the years that followed, the Stone Mill served variously as a police precinct station and carpentry shop. In the 1950s, the garden funded a well-intentioned restoration, but portions of the lowest level were altered considerably. Not until last year did this National Historic Landmark receive a comprehensive, modern restoration.

When I first happened upon the Stone Mill, the thickness of the walls and the riverside setting caught my attention. I learned that this was the third mill to be built on the site, and that massive water-powered grindstones once located in the basement had processed snuff for about 30 years.

When the garden's staff first contemplated a new preservation program in 2008, the millstones were long gone, but the exterior walls remained largely intact. Workers digging into the facade found the original mortar, made of lime and sand from the Bronx River—quite distinct from the cement-based mortar applied during the 1950s restoration. "We duplicated the [original] mortar," says Frank Genese, vice president for the garden's capital projects divison. "It creates a ripply dynamic … [and] makes it look like the stone is dancing on its own." When the sun shines on it, the facade turns a golden brown that shimmers.

Restorers ripped out the '50s-era windows, then returned to the original pattern of fenestration and placement of doors, and rebuilt the cedar shake roof that once topped the mill. Engineers also routed mechanical systems and duct-work through two existing chimneys.

To guide their work, crews relied upon historic black-and-white photographs discovered in a variety of public and private collections, among them the Museum of the City of New York, the New York City archives, the New York Public Library, the Historic American Buildings Survey, Lyndhurst (a National Trust Historic Site), and the private collection of garden historian Wayne Cahilly.

"Computers helped," says Genese. During restoration, he and his team used Photoshop, for example, to see how the finished mill would look. They assembled images to scale to determine the most appropriate colors and finishes. Before installation of an awning above the front entrance, they manipulated the images to inform placement and appearance.

In addition to architects and general -contractors, Genese consulted with contractors specializing in masonry restoration and historical carpentry. One carpenter found 150-year-old siding from a barn in Valley Forge, Pa., and used it to replicate the original wood floors on the main level, now a ballroom. Acquiring, installing, and sealing the flooring cost $160,000. But Genese says, "You really need people who understand the means and methods of how things were constructed then, and the materials used. You don't want a 'lazy restoration.' If you don't take careful steps, if you rush through jobs like this, you basically have a building that is not accurate."

The interior of the restored mill stands as a prime example of adaptive use. The three-story, 11,000-square-foot building, composed of local stone, now provides revenue-generating entertainment space, as well as offices for horticultural staff.

Genese estimates that the entire mill revitalization cost just under
$13 million. Exterior work complied with the stringent restoration guidelines established by the U.S. Secretary of the Interior, and interior work met the secretary's standards for rehabilitation. The restored Stone Mill has already earned LEED (Leadership in Energy and Environmental Design) silver -certification.

In vivid contrast to the Stone Mill, the Peggy Rockefeller Rose Garden splashes color across the easternmost part of the New York Botanical Garden. Knowledge about roses is not a prerequisite for a visit; you can learn all about the history and cultivation of those showy shrubs if you take the audio tour.

Designed in 1916 by the famed American landscape architect Beatrix Farrand and enlarged in phases, the garden didn't assume its current form until 1988, when David Rockefeller made a substantial donation in honor of his wife, Peggy. Then, in 2005, the unexpected happened: The City of New York adopted a public health law prohibiting the use of pesticides in open spaces, presenting the rose garden's caretakers with a new set of challenges.

"We were mandated to reduce our chemical usage," explains garden -curator Peter Kukielski, and that meant replacing 2,000 prized but pesticide-dependent bushes in the garden. He began contacting hybridizers around the world to solicit information about roses that didn't depend upon chemicals to grow strong and healthy. And his investigations eventually paid off with the identification and acquisition of 3,659 plants in 607 varieties.

"Ninety-five percent of the roses are brand new," Kukielski says. He and his team replanted the triangular garden (it covers slightly more than one acre) one section at a time, "so that it doesn't look all newly planted."

The results are spectacular. The garden is a light-filled oasis in a city of skyscrapers that block the sun. Of the more than 40 classes of roses, about 35 are represented here. Myriad colors—pinks, reds, yellows, whites—blaze during the summer months. I was fascinated by a few varieties, particularly Double Delight, which turns from white to red in the sunlight.

The garden received the 2010 Rose Garden Hall of Fame award, the only American garden to receive the distinction that year. The award recognizes "the significance of this [$2.5 million] renovation, which has resulted in creating a sustainable public garden, representing an outstanding collection of roses that provides the public the necessary knowledge to choose roses that can be grown without harming the environment."

Follow my example. Travel to the Bronx and discover your favorite corner of the New York Botanical Garden. It's a landmark designed for exploration, a treasury of surprises as changeable and dynamic as the city itself.

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