Jargon Watch: Vertical Gardens vs Vertical Farms vs Living Walls vs Green Façades

A living wall growing on the side of a building.

Valerio Gualandi / EyeEm / Getty Images

In his post New Vertical Garden Comes to Spain's San Vicente, Alex wrote "Vertical gardens are here to stay." Our editor in chief wondered if there was a contradiction here with our post yesterday Fix Our Horizontal Farms Before We Go Vertical, where I questioned the merits of vertical farming.

I pointed out that vertical farms, designed for food production, were a very different thing from living walls, which I thought Alex incorrectly called a vertical garden. But he is not alone; we did it in Madrid Gets a Vertical Garden Too and Ugly Cooling Tower Gets Vertical Garden Makeover in Spain. (Interestingly, all Spanish projects)

Living Walls

A living wall full of plants on a building.

Jean-Pierre Dalbéra / Flickr / CC BY 2.0

Properly, these Spanish projects installations should probably be called "living walls" rather than vertical gardens. Vancouver landscape architect Randy Sharp explains in Azure:

Green walls come in two main varieties, ac­cord­ing to Vancouver landscape architect Randy Sharp. His firm, Sharp & Diamond, designed the Vancouver Aquarium's 50-square-metre green wall of polypropylene modules filled with wildflowers, ferns and ground covers. A leading expert on "vegetated building envelope systems," Sharp divides these installations into green facades, where a structure fastened to the wall provides a trellis for vines and climbers planted in the ground or in containers; and the newer living walls, where a modular grid of wall pan­els - complete with live plants, a conventional soil or layered-felt growing medium, an irrigation and nutrient-delivery system, and a support structure - is attached to the building.

Patrick Blanc, the botanist who popularized the living wall, calls it Le Mur Végétal, or Plant Wall. It is usually fed by hydroponics and often uses no soil at all.

Green Façades

A chimney covered in plants in Paris.

dany13 / Flickr / CC BY 2.0

As noted by Sharp above, green facades have their roots in the ground and do not require pumps or technology to keep them alive. Édouard François has built a number of these; see Visiting Architect Édouard François In Paris

Harvest Green: Vertical Farm by Romses Architects wins Competition

Vertical Farms

A vertical farm growing lettuce in hydroponics set up.

sommart / Getty Images

Vertical Farms are, according to Dr Dickson Despommier, urban highrises devoted to producing food. Hewrites in an essay:

One vertical farm with an architectural footprint of one square city block and rising up to 30 stories (approximately 3 million square feet) could provide enough nutrition (2,000 calories/day/person) to comfortably accommodate the needs of 10,000 people employing technologies currently available.

All of these terms are pretty clear; the term "Vertical garden" is not, as gardens can be used either for ornamental, decorative purposes or for food production. Perhaps the term should be retired.