Before Tom and Phyllis McCasland moved to Preston Hollow from Oklahoma in 1998, they were already familiar with the Dallas Arboretum.

As Tom describes it, “It’s one of the finer things Dallas has to offer its citizens.”

The couple knows something about the subject, having traveled extensively in the U.S. and abroad, touring gardens at each destination. The more they traveled, the more grateful they were to have the Arboretum so close. They were so impressed that they decided to pay for the renovation of the sunken garden on the east side of the park.

“We feel strongly that this is one of the best gardens in the world. The Arboretum is a great asset, and we wanted to be part of it.”

Architect Warren Johnson, who is donating his time to the renovation, is overseeing the half-million-dollar project. Johnson says designing a garden within a garden is a rare treat.

“I like to think of these gardens as a living cathedral,” he says. “The site’s elongated shape, intersecting pathways and rounded terminus are reminiscent of a medieval cathedral’s footprint.”

The inspiration piece for the garden’s design is a procession of Italian jardinieres and geometric patterns shaded by towering trees. A central aisle steps down to the grass court’s congregational space, which is bounded by seasonal plantings, and herbaceous border, a hanging garden of Earthkind roses and a colonnade of sculpted plants.

Arboretum President and CEO Mary Brinegar says the sunken garden is a prime wedding spot but hadn’t been updated in 20 years.

“It was in need of rejuvenation,” she says. “What it needed was somebody who really believes in the dream, and the McCaslands do.”

In fact, Phyllis earned a Master Gardener certification because of her intense interest in plants and flowers. She says Arboretum is an oasis for nature lovers in a city not known for its natural beauty and notes that the variety of plants and flowers grown there might surprise visitors.

“A lot of people think because the climate is so extreme we can’t grow a lot of things, and that’s not true. It’s a challenge, but it’s there. It really helps beautify Dallas.”

“I think the color our garden has in the spring and fall particularly is just outstanding,” Tom says.

The McCaslands had been “Friends” of the arboretum for more than three years before making this donation. Phyllis said they chose this particular part of the garden for a number of reasons, not least of which is the unusual sunken aspect of it, which piqued their interest. They also liked the fact that it is in a “showcase location” for weddings.

“This will be an area that will be important in showing off the Arboretum, and we are proud to have it carry our name,” Tom says.

The dedication ceremony for the sunken garden is May 11, but it is already open to the public as part of Dallas Blooms.

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