The interior of the Mellon estate and library in Upperville, Va. (Marvin Joseph/The Washington Post)

After they married in 1948, the philanthropists Paul and Rachel Lambert Mellon began collecting art in earnest, though their tastes followed their own distinctive interests.

Paul Mellon, consummate equestrian and Anglophile, favored 18th- and 19th-century British paintings of landscapes and horses. “Bunny” Mellon, gardener, landscape designer and Francophile, was drawn to French paintings of flowers and idyllic scenes. Together the couple also collected Impressionists and Post-Impressionists and by 1966 had amassed enough paintings to lend almost 200 to the National Gallery of Art for an exhibition of French pictures.

Bunny Mellon (left), Paul Mellon and stepdaughter Eliza Lloyd in London on Dec. 11, 1964. (Associated Press)

Bunny Mellon’s lifelong passions for horticulture and art also converged in a parallel world. Over the years, she assembled one of the country’s most significant private collections of antiquarian garden books, manuscripts, modern volumes, botanical art, sculptures and objets d’art. Some of the illuminated manuscripts date to the 14th century, but the collection also includes floral works by Pablo Picasso and Andy Warhol. It became so large, and so important to her, that she built a library for it at her Upperville, Va., estate.

Oak Spring Garden Library was known among scholars, including a handful each year who were allowed to study there, but it was essentially a place of Bunny Mellon’s own creation and retreat. Almost three years after her death, the veil is lifting. The Mellons’ estate in the Virginia Piedmont is in transition from a private domain to an institution — the Oak Spring Garden Foundation — with ambitious plans to share its wealth of knowledge.

Sir Peter Crane is the new director of the foundation established by Bunny Mellon. He is photographed at the Mellon estate and library. (Marvin Joseph/The Washington Post)

Under its first president and administrator, Peter Crane, the foundation is planning to open the collection to a small colony of resident scholars, who will live in Paul Mellon’s converted broodmare barn. The entire 263-acre Oak Spring setting (once 4,000 acres) will become a venue for academic conferences, the first this spring.

Crane, an English paleobotanist, wants the foundation and its collections to foster study and debate in areas of keen interest to the Mellons, including garden history, botanical art, botany and horticulture, and sustainable agriculture.

Although not open to the public, Oak Spring is making its catalogue and some manuscripts available online. The foundation plans to lend to or lead exhibitions featuring the collection. The first show is underway at the New York Botanical Garden. “Redouté to Warhol: Bunny Mellon’s Botanical Art” runs until Feb. 12 and features almost 80 artworks, including botanical art, illustrated manuscripts and rare books. Crane calls it “a coming-out party.”

Cristoforo Munari. Still life with a quince, an apple, lemons, and three Chinese blue-and-white cups, ca. 1700. Oil on canvas. (Oak Spring Garden Library)

A life shaped by plants

Bunny Mellon laid the groundwork for the foundation before her death at age 103 in 2014. Paul Mellon died in 1999 at 91.

In the art world, the Mellons were major benefactors to the National Gallery of Art and to the Virginia Museum of Fine Arts in Richmond. He was the progenitor of the Yale Center for British Art.

Bunny Mellon kept a decidedly low profile — she was no Georgetown socialite — but her circle of close friends included Jacqueline Kennedy Onassis and the French designer Hubert de Givenchy.

“She didn’t define totally what she wanted, which I think was very wise of her,” said Crane, “but she did define what her hopes and wishes would be, and we are trying our best to measure up to that.”

Books from the Mellon estate and library. (Marvin Joseph/The Washington Post)

Crane, 62, is trim, bespectacled and silver-haired. To borrow from T.S. Eliot, he is “neither diffident nor ostentatious.” If you sat next to him on an airplane, you would have to wheedle his story out of him. He is a Fellow of the Royal Society, the venerable London-based scientific academy, and was knighted in 2004 for services to horticulture and conservation. He recently ended a seven-year stint as dean of the Yale School of Forestry & Environmental Studies and previously headed the Royal Botanic Gardens, Kew, and the Field Museum in Chicago.

He continues his lifelong research into fossil and evolutionary botany. He never met the Mellons but undoubtedly would have been a good fit with them because of his scientific acuity, tact and administrative skills. Like Bunny Mellon’s life, his has been shaped by a communion with plants. In fact, everyone’s life is, he says: “No one can opt out of their relationship with plants.” Plants clean our air and feed our bodies. That basic reality of life seems lost on a world mesmerized by the wonders of the digital age, but Crane seems determined to use Oak Spring to shout it from the treetops.

If you are lucky, like Bunny Mellon, you discover that plants also feed the soul.

Understated elegance

With New York architect H. Page Cross, the Mellons created a domain that was a successful synthesis of Virginia colonial and French provincial. What is remarkable, especially in the house, is its modesty. With its white-stained walls and the faint checkerboard patterning on the wooden floors, it is stylish but understated. The rooms are not too grand, the ceilings too tall or the ornament overwrought. Elegance trumps opu­lence.

The house leads seamlessly to the garden, which is defined by paved terraces softened by thyme, whitewashed stone walls, small ponds and espaliered fruit trees. In its structure and feel, it is evocative of a fine French country garden, though it is also inspired by medieval walled gardens. Two elements stand out: a long tunnel of clipped, white-flowering crab apple, which Bunny Mellon pruned fastidiously, and an inviting greenhouse-conservatory.

The exterior of the Mellon estate. (Marvin Joseph/The Washington Post)

It was through the garden, and often directly from working in it, that Bunny Mellon made her way to the library. It consists of two wings, the first a slant-roof gallery and office annex designed by the modernist Edward Larrabee Barnes in a blend of contemporary and vernacular design. A sympathetic addition, by local architect Thomas Beach, was added in 1997 and contains an entrance reading room with a second-floor mezzanine. It also includes rooms for reading and storing oversize books, maps and plans.

It is the old wing, opened in 1981, where most of the volumes are housed and where their owner gravitated. The books are kept behind banks of custom-made oak cabinets with folding doors. Above, more stacks run alongside an elevated walk. Picture windows look out onto Virginia hunt country.

The spirit of its creator hangs in the air: Tables are covered in tapestries, and chairs and settees, hard and soft, are clustered in cozy, eclectic groupings, just as Mellon had them. Her grand piano sits at the far end. Tony Willis, her librarian since 1980, says she used to play classical music for her own amusement.

She was most content, he said, when she would sit at the round white-oak table (made by estate carpenters) with a rare book in front of her and bathed in the mystical radiance of a large-scale painting by Mark Rothko. Predominantly yellow and dating to 1954, it measured a colossal (almost) 10 feet tall and 15 feet long and was considered one of the most important of all Rothko’s paintings. It sold after her death on the private market and may have set a record sum for a Rothko. One reported estimate of the picture’s value was $150 million. Titled “No. 20 (Yellow Expanse),” the oil-on-canvas was one of nine Rothkos bought by the Mellons in the early 1970s.

Today a full-size facsimile takes its place in the library.

Treasured tulips

The books and papers hold scientific, artistic and literary value as well as enduring practical advice for gardeners. Mellon loved those that documented the work of the great French fruit gardeners, especially Jean de la Quintinie, from the late 17th century, and Louis Claude Noisette, from the early 19th century. She put their methods to work in her own espalier-rich garden.

Pierre-Joseph Redoute. Tulips and roses, 1811. Watercolor on vellum. (Oak Spring Garden Library)

Some of the material was chosen for its cultural significance. Mellon was captivated by Tulipomania, the frenzied investment bubble for tulips in 1630s Holland, and she collected works that chronicled and, in some cases, fed the craze. The New York show includes watercolors of tulip varieties painted for contemporary nursery catalogues. One of the most sumptuous portraits of tulips forms part of the show and was painted by perhaps the greatest of botanical illustrators, the French court artist Pierre-Joseph Redouté. The watercolor depicts a grouping of languid and voluptuous white- and purple-flamed tulips rising above the artist’s more famous subject, old garden roses. The roses seem tame next to the tulips.

Crane shows a visitor around the library, but there is not enough time to begin to savor its treasures. There is a set of James Bateman’s “Orchids of Mexico and Guatemala,” 40 elephant folio plates and the largest botanical book ever published. There is Robert Thornton’s “Temple of Flora,” a book so lavish in its illustrations that it bankrupted the author.

The quality of the collection is underscored when Crane shows the reading room containing the full-size, four-volume “Birds of America” by John James Audubon. On this day it is opened to the plate on the bemaculated duck. Only a dozen or so sets are said to be in private collections. One sold for $11.5 million at Sotheby’s in 2010.

‘She spent time with them all’

For Mellon, the library was not simply about acquiring valuable documents. “Her collection was guided by precise objectives and unerring taste,” writes Lucia Tongiorgi Tomasi in the show’s catalogue. Tomasi is an Italian scholar who has studied at Oak Spring since 1992 and who wrote two of four books (one with Willis) based on the collections.

Willis, in an interview, explained Mellon’s approach to collecting. A dealer would send a book to the library on approval. Assuming she didn’t already own a copy, she would consider it based on its quality, how it related to her other objects, its condition “and just overall what she would learn from it and how it would help other people,” Willis said.

“She was very discerning, and she took a real interest in them,” said Susan Fraser, director of the botanical garden’s LuEsther T. Mertz Library, where the show is staged. “They weren’t objects she purchased and tucked away. She spent time with them all.”

Fraser said she was struck by the little knickknacks that Mellon had accumulated over the years, mementos of moments and friendships. One was a curio, a little greenhouse made of metal with topiary plants in it. It was not a valuable piece but was given to her by Givenchy.

Tomasi recalls being in the library one day when the patron came in with Jacqueline Kennedy Onassis. “Tony [Willis] wasn’t there, so I was showing to Jackie different books and manuscripts. She was a very sensitive woman and attracted to the beauty. I showed to her some of the most precious books in the library.”

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