Make Your Garden Look Bigger With This Smart Decorating Move

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NO ONE hesitates to deploy mirrors inside a house—lengthening a cramped entryway or bouncing light around a dim dining room. Why not in the garden, then, where a mirror could multiply lush hydrangeas, reflect cloud-dotted skies and make sunshine dance? Garden designer Toby Musgrave, the Copenhagen-based author of "The Garden: Elements & Styles" (Phaidon Press) considers looking glasses a fantastic way to play with your patch of green: "I like the idea of optical illusions—a bit of fun, drama and theater." Besides, an open-air mirror yields the same benefits as one indoors. A garden becomes more cozy and warm, said Karen Rogers, a London landscape designer, and the reflection "makes it actually look bigger."

Mirrors brighten an outdoor space while doubling the impact of flora and hardscaping. If your yard has a beloved focal point—a statue, water feature or flower bed—an outdoor mirror placed nearby can amp it up. Rogers imagines running a long example on a wall or screen alongside a swimming pool, visually echoing the water. "It feels more like an active space or a room if you’re using mirrors," she said.

If your retreat lacks an obvious centerpiece, a bare wall or fence presents a canvas to create one. Or, more subtly, mirrors can nestle into awkward corners or deflect attention from foul features. "If you have an ugly shed, place mirrors on its side to make the shed disappear," Rogers said.

Before settling on a site for a landscape mirror, Rogers tests out different vantage points to anticipate which vegetation will be reflected. For year-round charm, the designer strategizes views of evergreens, whether trees, shrubs or climbers. When a garden is mainly used during warmer months, she seeks to frame statuesque and colorful flowers such as alliums and tulips. Just take care to avoid doubling unsightly features like compost bins and drain pipes, says Musgrave.

Not any mirror will do. Musgraves cautioned that a household mirror "shoved in a garden will look awful pretty quickly." Rosanna Bossom, a London designer, hangs old cast-iron frames converted into outdoor mirrors that can withstand the elements and "weather beautifully over time." For a romantic, traditional look, Rogers hangs an arched window inset with mirror panes, which will resemble a door. In a modern garden, Musgrave prescribes stainless-steel or white-concrete frames.

Blasts of reflected direct sun can scorch leaves, says Rogers, who recommends installing mirrors in semi-shaded areas. And avoid placements that drill sunshine into guests’ eyes come sundown, Musgrave warns, unless you want your garden cocktail party to end abruptly.

Twilight presents another set of optical opportunities. Musgrave finds that draping fairy lights along a mirror's perimeter gives the reflected greenery an ethereal glow. And Rogers trains landscape lighting so it shines up on plants that come into view via a reflection for guests lolling on a garden bench, guaranteeing a pleasantly orchestrated summer evening.

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