By Robert D. McFadden

New York Times News Service

Rachel Lambert Mellon, an heir to the Listerine fortune and a horticulturalist, fine arts collector and philanthropist who redesigned the White House Rose Garden, died Monday at the Upperville, Va., estate that had been her principal residence for decades. She was 103.

Her death was confirmed by her friend and longtime lawyer, Alexander Forger.

Born into wealth, married to men with banking, oil and steel empires, Mellon, known as Bunny, had houses in New York and Washington, apartments in Paris and country seats on Cape Cod, Antigua and Nantucket, besides her estate in Virginia. Her friends were presidents, royalty, socialites and celebrities. Late in life, her support for the presidential aspirations of Sen. John Edwards of North Carolina made news when scandal engulfed him.

Mellon was the eldest child of Gerard Barnes Lambert, president of Gillette Safety Razor Co., whose father founded Lambert pharmaceuticals and invented Listerine. Her first husband, Stacy Barcroft Lloyd, was a Pennsylvania businessman and horse breeder, and her second was Paul Mellon, the only son of Andrew Mellon, one of the world’s richest financiers and treasury secretary to three presidents.

Fresh-faced, slender, ebullient, radiating confidence, she was a dazzling figure in a swirling cotillion or at the taffrail of a steamer. But beyond her carefree life of parties and travels, her real love was gardening — and she was good at it. She had been fascinated with gardens since childhood, watching the landscape man at her home in Princeton, N.J., studying prints of flora and pictures of gardens.

Though not formally trained, she had an instinct for horticulture. She read her way through the subject and learned about gardens firsthand in America, England, France and Italy. As a girl, she built miniature gardens in wooden boxes, incorporating stone steps, soil and topiary. Her first professional job, at 23, was a garden for designer Hattie Carnegie, who paid her with a coat and dress.

She designed gardens for dozens of clients, many of them her friends, and donated the payments to horticultural or medical causes. She shaped terrains, used trees as sculpture and horizons as frames, selected indigenous plants so they would flourish, formed interplays of shadow and light, and created subtle palettes of colors in the impressionist tradition of the landscape architect Beatrix Jones Farrand.

And she knew the Latin names: Ixia viridiflora, Platyclinis filiformis and Cymbidium Miretta. In an interview with Vogue, she complained that varieties of Alchemilla, a herbaceous perennial commonly known as lady’s mantle, were “well known in England and, I think, not enough appreciated in America.”

Like many other fabulously wealthy people, she lived largely out of the public eye, shielded by lawyers and public relations retainers, unlisted addresses and phone numbers, and retinues to shop and buy tickets. But she became known to many Americans in 1961, after President John F. Kennedy’s inauguration, when at the request of her friend Jacqueline Kennedy, she redesigned the White House Rose Garden.

Long used for presidential announcements and ceremonies, the Rose Garden, a plot 125 feet long and 60 feet wide outside the Oval Office in the West Wing, was created by Ellen Wilson, President Woodrow Wilson’s wife, in 1913, replacing a colonial garden planted in 1902 by Edith Roosevelt, President Theodore Roosevelt’s wife. President Dwight D. Eisenhower cut down the roses and turned it into a putting green.

Mellon crafted a central lawn bordered by flower beds in the French style, but with American botanical specimens: “Katherine” crab apples, little leaf lindens, diamond-shaped hedges of thyme, and on the corners Magnolia soulangeana specimens she found floating in Washington’s Tidal Basin. Roses were the primary flowering plant, but seasonal flowers were interspersed to add year-round color.

Her next work, the White House East Garden, was incomplete when Kennedy was assassinated in 1963. But President Lyndon B. Johnson’s wife, Lady Bird, another friend, asked her to finish it, and it was dedicated in 1965 as the Jacqueline Kennedy Garden.

For her work, Interior Secretary Stewart Udall gave Mellon the Conservation Service Award in 1966.

Rachel Lowe Lambert was born in Princeton on Aug. 9, 1910, one of three children of Gerard Barnes Lambert and the former Rachel Lowe. Her father became president of the family pharmaceutical firm, which was later Warner-Lambert and eventually Pfizer. She attended Miss Fine’s School in Princeton and Foxcroft, a girls’ preparatory school in Middleburg, Va.

In 1932 she married Lloyd. The couple had two children and were divorced in 1948. Lloyd died in 2008. She married Paul Mellon, the art patron and philanthropist who was heir to a colossal fortune, in 1948. He died in 1999.