"I'll never be done with it," Culp says, without a hint of resignation, for he understands what only the horticulturally hard-core do: A garden is never done, except on hyperactive HGTV, where, ironically, he was once a guest.
Culp, with decades of gardening behind him, actually sounds joyful about the prospect of working his back and arms and knees until he can't anymore, even joking, "If I retire, what would I do - garden?"
This is what he and Michael Alderfer, partners for 20 years, do. And until recently, when they hired a once-a-month helper, they did it all by themselves, something Culp hopes will inspire others.
"We started from nothing," he says. "We don't have an endowment. We don't have a staff. We had a passion."
Both also have real jobs.
Alderfer does interior plantscapes for museums, public buildings, and private clients. Culp teaches at Longwood Gardens; travels and does research and development for Sunny Border Nurseries in Connecticut; hunts for plants in the Netherlands, England, and Japan; designs gardens; lectures around the country; writes for garden publications, and is a bit of a celeb, having hobnobbed on camera with Martha Stewart no fewer than six times.
Now, after two years of writing on airplanes and in hotel rooms, Culp has produced his first book - The Layered Garden: Design Lessons for Year-Round Beauty From Brandywine Cottage for Timber Press, with local author Adam Levine and photographer Rob Cardillo.
Brandywine Cottage is the circa 1790 stone farmhouse adjoining two acres in Downingtown that Culp bought in 1990 and restored to include a multilayered garden, which he shares with hundreds of visitors a year from March through July.
"This time is for me," he says of fall and winter.
They, like spring and summer, are fully enjoyed in this special place, which had a spiritual resonance with Culp, a Quaker, from the moment he saw it. "I felt immediately at home," he says.
That is no surprise. Though Culp grew up in Reading and Tennessee, and lived in Georgia and North Carolina, Pennsylvania is in his DNA. His Kolb (later anglicized to Culp) ancestors - five brothers, farmers all - came to Pennsylvania from Germany 300 years ago.
In 1992, while visiting the certified-historic homestead of Dielman Kolb, one of the five, in Lederach in Lower Salford Township, Montgomery County, Culp had an epiphany. He decided then and there that at his own farmhouse, he would create a vegetable garden like his ancestor's.
It would become the heart of his Brandywine Cottage garden - utilitarian to feed the body, beautiful to feed the soul, surrounded by double borders on all sides. There would be layer upon layer of plants - not just any, but the best - that rise at different heights, pop through the year, and offer unusual forms, colors, and textures.
"More than just making sure one blooming plant follows another," Culp writes in his book, "layering is the art of creating a series of peak garden moments, the anticipation of which gets me out of bed in the morning."
He must leap out of bed these days. Fall's asters are pinwheels of pink and purple. The roses are fading, but the hips are grand. And as the statuesque Angelica drops dry seed on the ground, Culp proclaims these self-sowers - many a gardener's bane - "cheerleaders in the garden.
"I do a design and self-sowers lighten it up, making the garden not so studied," he says.
Culp is famous for the hellebores and snowdrops he breeds, and though they're sleeping now, thousands will fluff up the hillside and borders in late winter.
Then come the tulips, foxgloves, and alliums, forget-me-nots and salvias, and shrubs and trees galore - that he insists he can't live without. This garden, you see, is a pull on the heart.
Its naturalistic feel mimics his grandparents' small farm in Wears Valley, Tenn., in the Smokies, where he had his own pony, chickens, calf, and gardens, and sometimes the entire summer to wander the woods before returning home to Reading.
Later, while studying psychology at the University of Tennessee and working in the men's clothing business, he would recall those carefree days and a love bordering on, sometimes crossing into, obsession for ferns, wildflowers, berries, and greens.
"The call of the soil," Culp calls it, and he was always answering, visiting gardens, becoming a certified master gardener, working for a wholesale florist, doing freelance garden design.
In 1988, he moved back to Pennsylvania from North Carolina, officially career-changed. He began working at Waterloo Gardens in Devon, where he met Alderfer, taking horticulture classes at Temple University Ambler, and relishing a career that finds him answering "the call" even now.
No doubt Culp's answer has been intensified by two near-death experiences in the last two decades. He does not share the details, but perhaps they speak for themselves in this moment:
It occurred at Brandywine Cottage after a conversation between two gardeners - one a renowned expert, the other, in comparison, a know-nothing - that meandered pleasantly, as these things do, from one to two to three hours.
Visitor, leaving: "Are you going to work in the garden now?"
Culp: "No, I'm going to do some other things first and save the garden work till the end of the day. It's my reward."
Contact Virginia A. Smith at 215-854-5720 or email@example.com.