Roof Gardens: How to Create a Sky-High Haven

This article was originally published on Christie’s International Real Estate’s blog Luxury Defined.

 

With sweeping horizons all around and the urban streets far below, gardening in the sky presents a fresh perspective on any city. Architectural innovations—such as Thomas Heatherwick’s super-sized planted pergola in Tokyo, the pyramidal ACROS building in Fukuoka, Japan, and the much-loved High Line in New York City—have allowed roof gardens to draw our gaze up and away from ground-level gardening.

 

On a domestic scale, your private rooftop eyrie can be slick and svelte in metal and glass, or it can be a sky-high meadow haven for birds and bees. Either way, a roof garden provides precious outside space and the opportunity to press pause; invaluable in today’s bustling cities, and a trend that has landscape architects hooked.

 

New York roof garden with swimming pool

The roof garden at New York City’s Eastwick Residence is designed to be a seamless transition from the interior of the penthouse, and features a stunning reflection pool.

 

Room at the Top

“Here in New York City, we’re seeing more pools and spas on roofs, which is a truly spectacular experience, particularly at night,” says Cara White, principal at landscape design company Elevations. “There are also more elements to encourage four-season use, like outdoor fireplaces and firepits, and extensive outdoor kitchens. On a technical front, there are wifi-enabled lighting and irrigation systems, and more integration with home automation.”

 

The perfect example of this is the Eastwick Residence by HMWhite. The multilevel roof garden is “designed to weave diverse landscape typologies within, around, and above the contemporary penthouse.” It features a sun deck, a water spa, reflection pool, and a series of undulating knolls that “depict a rolling grassland prairie to visually increase the sense of spatial layering while subtly masking building mechanical systems.”

 
Eastwick Residence
 
A sunken dining terrace, a sun deck, a water spa, and a raked “lawn wedge” for lounging are other features of the rooftop garden at New York’s Eastwick Residence.

 

 

For Sera Rogue of Red Fern Brooklyn, rooftop design is all about maximizing space: “In New York City, space is at a premium so I encourage my clients to use every inch. We like to feature plants that clients see in nature at their farms or near their beach houses. A rooftop oasis lets you relax and recharge when a weekend getaway is out of the question.”

 

The Sky’s the Limit

Rooftop gardens can sometimes be tricky to create, and expert advice on weight loading and construction logistics is needed, but the design opportunities aren’t restricted to contemporary apartments. In London, award-winning garden designer Charlotte Rowe has created roof terraces and gardens in some unexpected locations—including the old boatsheds at Eton College in Windsor, a converted 19th-century dairy by the River Thames, and several Victorian buildings. And with architects and high-rise developers now incorporating rooftop gardens into their blueprints, there’s ample scope to bring more nature into the sky.

 

London roof garden with wicker furniture

Charlotte Rowe transformed this 1,400 sq ft (130 sq m) roof terrace in West London into seating areas with decked seats, wicker furniture, a wooden pergola, and a herb garden. Image: Clive Nichols.

 

So, where to begin? White suggests taking time to understand the nuances of the space, and how and when you’ll use it: “Roof terraces can have microclimates, so get a sense of where the breeze blows too hard at cocktail hour.” Meanwhile, landscape designer Jeffrey Erb starts by responding to the surrounding vistas. “There is this incredible connection between whatever is in your space and what lies beyond. For example, add an element of water to your design and suddenly you’ll feel more connected to the river that’s in view. The same thing can be done with architectural features.”

 

Although Erb finds that even clients with an eclectic interior style prefer a clean, modern look for their rooftop space, Rogue encourages a less rigid approach: “We’re moving away from sharp edges and industrial elements, and wild textural plants are now replacing cookie-cutter boxwoods. Organic materials are softening the backdrop of steel and glass, and natural woods like cedar and teak appeal because the patina evolves over time. Clients want to explore edible gardens and meadow-style plantings, and there’s now a desire to integrate greenery throughout the space, using low built-in planters, vertical green walls, and vine-covered pergolas.”

 
 
Rooftop seating and plants

Careful planting brings a welcome touch of nature to an urban roof garden in Charlotte Rowe’s London creation. Image: Clive Nichols.

 

Shadow Dance

Shadows are another device that Erb uses to introduce depth and visual interest. “Shadows can be created by plantings, or by pergola rafters dancing across a paved surface; even fencing or statues will cast intriguing shadows. The vertical components in an outdoor space create a sense of drama, too,” he adds. “If you have a view of a bridge or a beautiful skyline, we can use vertical elements to frame and enhance that view.”

 

Rogue always impresses on her clients the need for cover. Lattice screens, planted pergolas, retractable awnings, slatted fencing or steel cable grids all provide privacy and shade, combined with a lightweight or ‘floating’ floor: possibilities include quartzite or porcelain pavers, or decking in timber, aluminum, or recycled Trex.

 
New York City rooftop with trees and seating area

Designed by Elevations, this rooftop space aims to “fuse horticultural and architectural sensibilities,” resulting in an outdoor haven that inspires a sense of place.

 

Finally, plants, which are integral to the success of any rooftop space. At the High Line, the mix of perennials and grasses chosen by planting designer Piet Oudolf draws from North America’s indigenous prairie flora, and makes it perfectly adapted to the city’s variable climate. “Beach planting also works in a roof garden, because maritime plants cope well with wind,” says Rowe, bringing a flavor of the Hamptons to London or New York City. She uses a simple but dynamic planting palette: “Not too many varieties, and plenty of rhythm and repetition. We also prefer multistemmed trees because they don’t wobble around in the breeze.”

 

Rogue uses evergreens to buffer sounds from street level, underplanted with sages and colorful coneflowers, while Erb recommends grasses such as pennisetum and carex that “catch the wind and move beautifully on rooftops.” These simple combinations look completely at home under an open sky.