Andrea Filippone loves roses, but so do the deer that pass through her gardens almost every evening. “I have 40 or 50 that come across the property every day,” she said recently, staring out the French doors that lead to her central courtyard. “I can see the hoof prints right up to the front door.” So 10 years ago, she pulled them all out, and replaced them with boxwood.

There are more than 150 commercially available boxwood varieties, which come in many sizes, shapes, leaf forms and colours. And boxwood contains alkaloids that are toxic to deer, as well as humans. It also has a pungent odour: Oliver Wendell Holmes called it the “fragrance of eternity”; others say it smells like cat urine. You decide.

“My plant palette is limited to what the deer don’t eat,” said Filippone, 50, a garden designer and antiques dealer with a degree in architecture from the Graduate School of Design at Harvard. So she also planted hundreds of allium, nepeta, Solomon’s seal, jack-in-the-pulpit and hellebore. Having limited choices made her think harder as she designed the courtyards and gardens around this compound, which includes four 19th-century barns and a country house with open rooms and floor-to-ceiling French doors and windows.

She and her husband, William Welch, a designer, had already treated the outside walls of the buildings with an olive-gray stain, which weathers and, unlike paint, does not have to be reapplied every few years. It also looks old.

“My goal was to make it look like it had been here a hundred years,” said Filippone, speaking of the house they built to suit the old barns and the gardens. She and Welch bought this 35-acre abandoned dairy farm in 1994. “It was the architecture of the barns that led me to create rooms outside.”

Boxwood fits perfectly, because its various forms can be planted to form green walls and allees, low borders or tall pyramids flanking a doorway. “I love to work with green, all its different variants – gray-green, blue-green, chartreuse, as well as the different textures and different-size leaves,” said Filippone, who recently started her own firm, AJF Design.

Filippone, who is a director of the American Boxwood Society, started a boxwood nursery here three years ago, to explore the plant’s many forms and uses. She is also doing research with Eric T Fleisher, a Manhattan horticulturist and soil expert, to see if building up the natural organisms in her soil, by using compost, teeming with beneficial organisms, and watering plants with compost tea – an aerated solution of this rich compost, mixed with humic acid, kelp and molasses – will produce healthier plants.

Plants with healthy root systems, Fleisher explained, not only retain more water, but send more plant sugars out to beneficial bacteria and fungi, which in turn protect plant roots from disease and predators.“It’s a whole system,” he said. “We’re just trying to mimic what’s in nature.”

Reducing water helps

As Filippone has reduced water, and stopped fertilising with aged manure, her boxwood seem to be thriving. Boxwood is a tough shrub, but shearing it into balls and hedges stresses it, and many people overwater and overfertilise because they don’t understand the plant’s needs.

In time, these practices degrade the plant’s immune system, making it vulnerable to insects like leafminer, mite and psyllid, and diseases like leaf spot, canker and boxwood
blight.

English boxwood (Buxus sempervirens Suffruticosa) is prone to boxwood decline, in which mature shrubs turn brown and brittle, the foliage wilts and, in severe cases, the plant dies.

Interestingly, in the wild it doesn’t show any of these problems. Fleisher rarely shears her boxwood, either, except to remove the odd branch here or there. The collection, which has 179 taxa (or kinds) of boxwood, is the most diverse in the world.

Many of these plants, which are more than 40 years old, grow to 12 or 18 feet tall; some are 15 feet wide. Some are tall and skinny, others broad and rumpled; some are naturally rounded, and others sprawling, almost like groundcovers.

“People want to shear the boxwood because they think it looks unkempt – a man-dominating-nature kind of thing – so they cut the leaves, which is life to a plant,” said Batdorf, who has overseen this collection for 34 years.

Standing by a big English boxwood at the arboretum a couple of weeks ago, he snipped through a few leafy branches, clipping off leaves as well as twigs. “Every time you cut, one branch becomes four, five or six branches,” he said, “which makes branching so dense, light can’t penetrate.” Lack of light and poor air circulation encourage disease and make it hard for new leaves to grow.

Both Batdorf and Filippone hear tales of woe from homeowners who have tended boxwood for decades and “suddenly” have problems. It’s the accumulation of bad practices over time, both believe, including too much water, fertilizer, shearing and mulch.
In the process of rethinking her gardens, Filippone discovered that succulents are of no interest to deer, either.

So she has replaced the flowers she used to plant in her antique cast-iron urns with big, sculptural agaves, some with yellow and green stripes, some blue, some as curvy as an octopus.

“My annuals and perennials used to fry, because cast iron gets so hot in the summer,” Filippone said. “But the agaves love the heat. And I only water once a week.”

The varying greens and textures of her boxwood were beautifully apparent on a misty, overcast afternoon, following a torrential downpour. Instead of using English boxwood, which yellows in full sun and is prone to disease, she is experimenting with other varieties to see how they do in light and shade.

She began by planting Winter Gem, an Asian variety with bigger leaves and a more open habit than English boxwood, as a hedge around two sycamore trees in her south-facing courtyard. “But I don’t like it very much because it doesn’t keep its colour in winter,” she said.

“It goes a little yellowish-brown. I thought I was doing something wrong, but that is its tendency.”

Around the same time, she planted Justin Brouwers, a compact, mounding type, along the bed where she used to have her roses. It now forms a low, pleasantly rumpled hedge around purple alliums and a brunnera called Jack Frost, which has silvery leaves.

“Justin Brouwers looks like English boxwood, but it has that beautiful mounding habit, naturally,” Filippone said. It also keeps its colour and doesn’t brown out, as English boxwood does, under winter sun. She used Justin Brouwers to frame a geometric pool as well, in the white garden on the east side of this compound.

All about these many gardens, tucked around doorways and windows, in sun and shade, are wonderfully different boxwood: Rotundifolia, named for its round, dark green leaves; Green Mountain, a pyramid whose dark leaves stay green all winter; Grace Hendrick Phillips, a virtually pest-free conical dwarf.

Stone walls, topped with boxwood or catmint, with its billowing blue flowers, lead to other gardens up the terraced slope, including a potager, or kitchen garden, walled by privet. Inside these green walls – all edged by Justin Brouwers and accented with Jensen, a blue-green variety – are espaliered apple trees and geometric beds of edible plants, from rhubarb and beets to purple mustard greens.

Stone columns, 19th-century water carts, urns and deep bathtubs that call out to gardeners with aching joints are set about in the barns and greenhouses, which are heated by solar panels.

But the most restful place to sit is in the courtyard, surrounded by boxwood, in all its many greens.

New York Times News Service