Winter challenges gardeners’ fortitude

? As shredded leaves fill the compost heap and the asters and toad lilies bloom their last, it can be tempting to simply batten down the garden and retreat indoors for the winter.

But now is the time that tests a true gardener’s mettle, says Pennsylvania garden designer David Culp.

“I like the challenge,” he said. “You have a great sense of accomplishment when you can take whatever nature throws at you and bend it to your will and make a garden.”

The best way to find ideas for a winter garden? Look at them, he said. “I learned by traveling in the wintertime.”

Here are some things to think about as you start work on perfecting your winter garden:

Structures: With flowers and foliage gone, it’s the shapes — borders, paths, trellises, walls, arbors, steps, the architecture of the house — that tell all about your garden. Consider paths: A straight one speaks of formality, Culp said; it leads to a point, which needs some sight — a fountain, sculpture, topiary, gate — to focus it. Allees — rows of shrubs or trees on either side of a straight path — “are best in the winter, because they link the parts to the whole,” he said. “In winter, with no leaves, they show the rhythm more clearly.” A path that curves is more informal, leading you through the garden. Either way, winter throws a spotlight on the craftsmanship of paths, patios and walls. Well-laid pavers or stones are more interesting than plain concrete.

Structural plants: In the winter, “you’re looking through a different set of eyes,” Culp said. “You’re looking for texture, the silhouette of the shrub or tree itself, the play of light.” Look up. See the shapes of your tall trees against the sky. Then consider the plants that draw your eyes down. Take plants such as red-twig dogwood and mass them, Culp said, so they will have impact as they stand through the winter. The Asian white birch Betula platyphylla var. japonica ‘Whitespire’ looks better in groups or groves, he said, so “they don’t stand out like a sore thumb.”

Perennials: “Leave things standing that you can see through the winter,” said Julie Marzahl, who with her husband, Stephen, shares the landscape design firm Creative Environments Group Ltd. Sedum, for example, gets “nice little snowcaps.”

Planning for the winter garden — because it forces you to think about form, structure and the other big issues of garden design — has a larger payoff. “If you can say the architecture and lines of the garden are fine in winter,” Culp said, “your garden is going to be fine in June and July.”