Skin of Architecture: Green 2

Source: architectural-review.com

This small urban family house in Saigon won a Commendation for AR House 2011. The architects were inspired by the Saigon residents' preoccupation with balcony planters.

This habit of filling every nook and cranny with innumerable varieties of tropical flowers and plants means that many of the Saigon's most densely populated streets are among the city's greenest roads. ---The Architectural Review, 27 July 2011

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Source: jame.silva Flickr

The Green Side-Wall, Avinguda de Josep Tarradellas, Barcelona, Spain designed by Capella Garcia Arquitectura

It is the pioneering project of a new field, coined ‘vegitecture’ by the architects. This new design concept is essentially a large-scale free standing green wall that acts as a protective layer to its adjacent building. The wall has its own drip irrigation and automatic fertilizer system, and even integrated nesting boxes. The floors are internally connected by stairs — this greatly reduces the cost of maintenance and replanting, which is usually done externally via specialized equipment and labour. Also, the floors are designed with benches and fountains to create a unique urban park-like setting. -- The Pop-Up City

Source: Edouard François archdaily.com

Tower Flower, Paris, France, 2004 designed by Edouard François

The tower is the vertical continuation of an adjacent park. Its giant flower pots, hanging from the balconies, were inspired by Parisian window planters that can be in themselves botanical treasures. These façade elements were one of the first applications of Ductal (by Lafarge). The social housing is freed of all bearing walls. The inhabitants enjoy the rustling of bamboo and a light filtered by the foliage. -- ArchDaily

Source: architectural-review.com

To a larger scale, architect Edouard François proposed this residential tower in Nantes, France.

The 17-story structure is ringed with elliptical balconies implanted with chasmophites - plants that thrive in arid, rocky, mountainous situations.
Drawn from the collection of the Botanical Gardens in Nantes, the hardy, low-maintenance plants will be cultivated in long stainless-steel tubes attached to balconies, and in time will form a shaggy green corona around the building -- Architectural Review, 18 August, 2011 

Source: nytimes.com

To put a practical spin, Dickson Despommier, a professor of public health at Columbia University envisions a  'vertical farm' in the city. Read an article in New York Times.