Restoring a du Pont garden in Delaware to its former glory

Hagley is one of the lesser-known estates developed by members of the du Pont industrial dynasty in and around Wilmington, but, in one respect, it is the most important.

It was here, in 1802, that company founder and French émigré E.I. du Pont settled, building a gracious beige stuccoed country house on the banks of the Brandywine Creek as part of Eleutherian Mills, the gunpowder works that grew into the corporate giant DuPont.

Hagley's main ornamental garden, recently replanted and revived, is based on the type of formal fruit and vegetable garden that the company patriarch would have known in his homeland, full of espaliered apple and pear trees basking in the sun. But it is the shadier garden on the other side of the house, occupying terraces that descend to the creek, that is far more secret, mysterious and alluring.

This is the Crowninshield Garden, built as a neoclassical ruin almost a century ago and now a real one, left mostly untouched for more than six decades. It is beginning to stir from its slumber.

Over the last couple of years, director of gardens and horticulture Paul Orpello and a small gardening staff have started to remove the porcelain berry, bittersweet and other monstrous vines that have smothered the landscape, partially revealing the contours of the terraced landscape along with its jewels.

At the base of a steep hill directly below the house, Orpello points out freshly cleared areas where long-dormant spring blooms, snowdrops, snowflakes, Virginia bluebells, trillium and hesperis have returned after decades underground. We pass a pair of the largest parrotia trees I have seen, the size of red maples but with their distinctive mottled, sinewy bark.

Much is still hidden, and, as such, it is hard in one visit to discern the interconnectedness of the garden, its unfolding design narrative, but as we spend more than an hour threading our way through the seven acres of hillside paths (like mountain goats, carefully), we come upon garden features that still conjure their magic.

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At various points, imposing iron cauldrons once used in gunpowder manufacturing rest on walls cloaked in vegetation. In one of the least weed-infested areas, a large formal pond — the Lower Pool — is framed by a high stone wall, with arched grottoes and capped with a balustrade. The drama is heightened by the blanket of duckweed that has turned the placid, still water a surreal shade of green.

Elsewhere, we came across a high facade of brick and stone, part of the Refinery Terrace that clearly defined an important space in the hierarchy of the garden. In some areas, trees have pried loose the masonry; in others, massive stone steps have been dislodged by time. Orpello led me to a sunny, open area marked by stone and concrete columns, evoking a Roman atrium, with remnants of elaborate mosaics on the ground. On a stone table supported by carved griffins, fragments of other decorative stonework are placed. He calls this the “Pompeii altar,” which seems to amplify the eeriness of the place. Self-seeded mullein has grown up around a cracked but intact mosaic of Pegasus.

This remarkable landscape was made in the 1920s and ‘30s by Louise du Pont Crowninshield and her husband, Frank Crowninshield, a member of Boston’s elite class who had been, among others things, one of Theodore Roosevelt’s Rough Riders.

Why a neoclassical garden when Colonial Revival was all the rage? The couple had visited Renaissance villas around Rome. Edith Wharton had written a highly influential book on Italian villas, and many industrialists were shaping their gardens in the Renaissance style, including Pierre S. du Pont over at nearby Longwood Gardens.

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What was different about the Crowninshield Garden was that it was built not as a polished Beaux-Arts confection but as a stylized ruin, with broken columns and lost stucco and brickwork made to look timeworn.

There is another ghost at play here. The heart of the garden encompasses a major element of the powderworks, a complex known as the Refinery. In 1890, its magazine, with 100,000 pounds of gunpowder, blew up. The structure was destroyed, 12 people were killed and the explosion could be heard in Philadelphia, more than 30 miles away.

The mansion survived relatively unscathed, but its du Pont family members moved out.

The Crowninshields came to it after the mills closed in the early 1920s but used it only for a month or so in the spring and fall. They would arrive with a full entourage of staff, and the garden, once finished, became a perfect stage for entertaining. The saltpeter kettles, repurposed as garden torches, were filled with fuel and lit, and their light flickered on an array of classical statuary, columns, urns and the like.

Although the evening soirees were hardly bacchanalian, the Crowninshields "were of a social set that absolutely loved to entertain," said Jill MacKenzie, executive director of the Hagley Museum and Library.

In the 1980s, MacKenzie was down in the Mosaic Terrace, there was still some statuary, and old rose bowers and irises were in bloom. "At that moment, I thought I had been transported to someplace else," she said. "It was the most magical place I had been in."

The idea of bringing back such an enchanted garden is an intoxicating one. The actual process is far more sobering. I told Orpello that just to remove all the weeds and keep them at bay would be a herculean task. He seemed unfazed. The gardeners are equipped with flame weeders, he replied. "If I can get it hot enough, I can kill the roots."

The garden's rehabilitation may well reflect the aphorism that perfect is the enemy of good. Orpello is not looking at some pristine return of the freshly built garden.

But the work has begun — not just the vine and weed clearing, but also the development of a five-phase, $26 million plan to revive the Crowninshield Garden. It will include modern plants better able to look after themselves and stay in bounds.

“We know it’s going to take a large fund-raising campaign, but we believe there are people who have this appreciation for hidden gardens like Hagley,” MacKenzie said.

Orpello also anticipates ranks of volunteers stepping forward; the Delaware Valley has more than its share of people who are passionate about gardens and horticulture. "There's nothing like this in the States, no postindustrial site reimagined in this way," he said.

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The first task before any serious work can begin will be to stabilize structures and address sinkholes and other pitfalls.

The process, MacKenzie said, will be “almost like unwrapping something and finding out truly what was underneath.”

Adrian Higgins specializes in writing about gardening, landscape architecture, and related environmental issues for the Washington Post.