Maintaining the grounds of the largest formal French model in North America

A Toro walk-behind mower with attached sulky is used to mow this area of the grounds at Nemours.

The 222 acres of grounds and gardens at Nemours Mansion & Gardens ( are among the nation’s most extravagant and extraordinary. The Wilmington, Del., estate of late industrialist and philanthropist Alfred I. du Pont sits proudly behind his namesake Alfred I. duPont Hospital for Children, and the mansion and grounds recently reopened after a $39 million private restoration funded by the Nemours Foundation. The work included excavations, landscaping and repair to the 800,000-gallon reflecting pool. Inside the mansion, electrical systems were updated, and statues, paintings, furniture and tapestries have been refurbished.

A Genie lift used to help prune the large juniper allee.

Completed in 1910, Nemours Mansion, a Louis XVIth-style French chateau, is named for the French town also in duPont’s great-great-grandfather Pierre Samuel duPont de Nemours’ name. House tours cover 70-plus rooms, occupying nearly 47,000 square feet of the finest furnishings, furniture and art, and bus tours wind through the lushly landscaped gardens and wildlife-filled grounds. The revitalized gardens, the largest formal French model in North America, are inspired by the Petit Trianon at Versailles. Covered in 23 karat gold leaf, Henri Crenier’s statue Achievement is the centerpiece.

A crew of nine full-time employees along with one seasonal employee and one summer intern maintain the mansion’s grounds, but not those of the hospital property. There’s also a separate plumber to do fountain work, a carpenter and a handyman.

Beginning in 1996, the turf and garden work was outsourced for a 10-year stretch. For the last four years, the responsibility has been returned to the in-house staff. “They took a hard look,” says Gardens Supervisor Ken Barker, who worked for 26 years at neighboring Longwood Gardens and was involved at Nemours before and after the changes. “They were not spending much money, and the place went down. Then, we became part of the restoration. We hired people and bought equipment.”

That equipment includes Toro mowers, a 60-inch Z Master and others with 48 and 72-inch cut capabilities. There’s also a 12-inch GroundsMaster 4000-D four-wheel drive used to mow buffer areas, and four push mowers. There are six Echo weed wackers, and the crew gets around on seven E-Z-Go golf carts. There are also backhoes and a skid steer. “We have a little bit of everything,” Barker says.

“We’ve taken control,” adds Ric Larkin, resident horticulturalist, who had worked for private estates before, including a 23-year stay with another duPont family. “Once we opened back up to the public, we had to bring it back to what it had been.”

The next phase will focus on what are called the Southern Gardens, which have perennials and annuals framed with boxwood hedge. The boxwood is scheduled to be removed and replaced with new boxwood.

A crew member mows with a Toro Z Master with 60-inch deck.
Ken Barker, garden supervisor, with one of the larger beech trees on the property.

The initial renovation focused on The Long Walk, which stretches from the vista at the base of the mansion for a third of a mile down to the Temple of Love. There’s still work within that mile that remains unfinished like the restoration of the 1-acre Reflecting Pool. From the two long sides, there are three alleys of trees, mostly oaks, chestnuts and cypress, all intentionally planted to draw your eyes to focus on the center. In the Sunken Garden, all the walls were rebuilt, and a new irrigation system installed to water new plantings.

Others areas, like the Maze Garden, reflect incredible restoration efforts. The Maze Garden, in particular, was restored to the fashion duPont preferred. Between the flagstone mosaics, once again there’s turf (as mortar) where there had been concrete. Of course, all of it needs to be mowed with a push mower, and the whole area also requires regular edging.

The northern buffer is largely conifers, mostly old spruce trees. There, the crew mows, but it doesn’t fertilize for weed control for about 50 or 60 feet off the buffer. In all, five crew members are mowing the grounds four to five days a week between late spring and early summer.

Nemours still outsources some of the specialty work. Weeds, Inc. in Aston, Pa., fertilizes the turf in the Long Walk and also sprays ponds and pea gravel walkways, and Bartlett Tree Experts in Wilmington handles the hardwoods.

The irrigation system is by Hunter Controls in Bethesda, Md., but the on-site crew can also uses remote controls from its offices to control fountains. Barker says the irrigation system is set on sensors, so if a big storm rolls through, the system shuts itself off. “It’s quite sophisticated, probably more than we need,” Larkin says. “We’re learning as we go.”

Elsewhere, the grounds crew prunes 4 miles of hedges, including privets, boxwood, yew, stephanandra, barberry and juniper, three to four times a season. The main drive is maple-lined with October Glory. Most of the trees on the estate are oak, linden or aesculus (horse chestnut).

The grounds around the new $8 million visitor’s center, while not historic, have added to the crew’s workload. There, Larkin says there are a lot of planters, even tropicals. Gardeners do not grow flowers on-site, except for red canna; there are 2,000 of them alone around the Temple of Love. Dug up in the fall, they’re overwintered in cool, dry conditions and replanted in May. Overall, 17,000 annuals are planted a year, including begonias, andonia, red salvia (3,000 of then in the Maze Garden alone), impatiens and lantana.

Equipment includes a walk-behind 48-inch mower, as well as four push mowers.

“This is a world-renowned garden,” Barker says. “You don’t find them everywhere. It has structure and formality, with the Collanade and the fountains. I’ve been to Versailles Gardens, and I’ve seen them. This is just a piece of it. It’s getting there. It’s still growing into itself.”

In the fall, there’s leaf clean up and mulching for reuse. The crews start raking leaves in October, but the last leaf isn’t picked up until planting begins in May. There are lots of pin oaks, and since they hold their leaves the longest, it make scheduling a single cleanup difficult.

Over the winter, the crew does its planning and ordering of annuals, and then come spring starts its plantings around the mansion house, drilling holes after the earth has been tilled.

“It’s a great place,” Larkin says. “And we’re here at the ground level.”

The author has been published in national and regional magazines as well as daily and weekly alternative city newspapers.