The Vertical Forest

The Hanging Gardens of Babylon are famous, although no one knows where they were physically located. There is even some doubt whether this garden ever actually existed, as it was only the Babylonian priest Berossus who wrote in 290 BCE from first-hand (?) sightings. Regardless, so many of us want it to be true, and try to make it true of our own ‘castles,’ even if only in small part. 

I have mixed feelings about it. I love plants. Plants are gods, replacing wastes with the vapors and substances needed by the living. We keep small plants indoors for their ambiance, and larger perennials in landscaping features to hide rude concrete and steel and to provide for wildlife. But we fear large trees next to our houses and paved driveways, and are right to eschew them. Only shrubs and small tree species are allowed within falling-limb and pavement-buckling distance of most abodes. But mirages of hanging gardens still sway in the whims of my daydreaming mind.

An Italian architect named Stefano Boeri and his staff designed two residential towers in Milan, Italy, called Il Bosco Verticale, or The Vertical Forest. At 80 m and 112 m in height, they host appx 20,000 plants in balcony containers. This greenery is comprised of perennial herbaceous flowers, shrubs, and small and medium-sized trees. I think it also includes lianas, but that is not stated in media articles. The two towers are sweet, if not exactly lush. For example, the greenery is in spots rather than sweeps and washes, as it appears that nothing is allowed to grow on exterior walls. Furthermore, gardener pruning keeps plants well separated.

https://www.cnn.com/style/article/riba-vertical-forest-stefano-boeri/index.html

The carbon footprint of the spectacle has been assessed, concluding that it would take many decades for its flora to offset construction impacts and maintenance costs. This is in large part due to the additional structural needs for supporting the heavy weight of the plants and their containers, potting media, and water. In addition, the large balconies, being appx 40% of the total floor space, are quite heavy.

Another limit on the carbon footprint offset is the need for three gardeners working nearly year-round to clip the flora. Firstly, most plants really do not need to be clipped. Secondly, this keeps exterior walls possibly overly exposed to the elements. Thirdly, gardeners are expensive. Are three gardeners working nearly year-round really necessary? For example, one video depicts gardeners pruning low-growing flowering plants even though most perennial cultivars exhibit self-limiting growth simply by dying back in the winter. Planting small and medium-sized trees also appears to be a mistake, both because of their weight and the need for artificial irrigation and pruning. Shrubs grow plenty large on balconies, and annual pruning easily ensures that they do not grow too heavy.

The videos and articles I have seen do not mention how the plants get watered. Watering can be done automatically with drip irrigation systems, or by shunting rainwater into plant containers, or by choosing drought-tolerant cultivars that are fine when watered only when it rains. Too, water is heavy, so keeping plants small and maintaining only relatively small plant containers reduces the load on and size of such balconies.

Thus, the building’s carbon footprint can be reduced substantially by growing smaller, more drought-tolerant plants in smaller containers on smaller balconies.

Another weakness of the Milan Vertical Forest is the value placed on the amenity that the vegetated balconies were supposed to offer residents. The architect doubtless envisioned residents having breakfast and dinner there, relaxing outdoors with a good book, or perhaps having a smoke while enjoying the scenery. However, Milan’s climate is evidently too chilly for most of the year, so residents remain nearly entirely indoors when home. Conversely, some cities are simply too hot for hanging out outside during summer.

After I ran across and enjoyed several Vertical Forest articles and videos, several people coincidentally posted articles on it on Facebook. A bunch of sharks on one site piled on the idea in a virtual feeding frenzy, falling all over themselves to pan the idea. It never ceases to amaze me that invention is literally always attacked by those who are unable to understand that prototypes are deliberately designed to find their own flaws so that future editions can be informed and become better. You can see some of that in the above text where I mention how some of the invention’s flaws can be easily mitigated. So, I decided to review the cartilaginous fish attacks to see if they had come up with any issues that I could not think of potential solutions for off the top of my head. Here goes:

AM: “Structure engineer had their math cut out on this project…”

Buford: Hmm, what does this comment mean, anyway?

 

WS: “I can only imagine the insect problem in this building.”

Buford: Why would the “insect problem” be any different in this building than in any other city building? For one thing, if this building were plopped down anywhere that I have ever lived, it would have many birds and lizards consuming the insects. Whatever, there are more plants around my single-story house than there are on the balcony of any of the vertical forest’s apartments. Dumb.

 

MO: “When good intentions go bad..roots verses concrete.. good luck if you’re living in that.”

Buford: Roots are not a problem in the proper plant containers. Duh.

 

AR: “It may work if it was designed for that purpose the roots may be controllable with the hydroponic system however all that being said moisture and concrete are not long term friends…”

Buford: Hydroponic systems are heavy and would have large labor costs in a vertical apartment forest. FYI, concrete and moisture are actually lovers – concrete continues to set long after you think it is dry. Indeed, concrete sets better underwater than under air. And anyway, if moisture were such a problem with buildings, then why is it so popular as a construction material all over the world? Do your due diligence.

 

PM: “…the cyclic loading from winds going through the trees couldn't possibly have been accounted for.”

Buford: This comment cracks me up. LOOK at the picture! In the first place, there is no more windage with than without the veggies. Secondly, PM is evidently not really aware of just how thorough professional architects are. THEY do THEIR due diligence.

 

WL: “In fact it might not even be possible to safely construct and operate such a building. The water it would require would be terribly heavy and difficult to manage.”

Buford: In fact, it was indeed safely constructed and is currently being safely operated because it was designed by architects who did their homework, and it was permitted by professionals who did their due diligence, too.

 

MEW: “This cannot be a good thing.”

Buford: What cannot be a good thing? We cannot read your mind.

 

MMB: “Well, you also need to look at the long term side effects...”

Buford: What long-term side effects? Oh, and can MMB possibly imagine that one of the purposes of prototypes is to “look at long-term side effects?”

 

BKB: “…it wouldn't last one windstorm in Alaska…”

Buford: This comment cracks me up. BKB apparently thinks something like this might even be designed for an Arctic or Antarctic locale (!); or that it is not a good idea for Miami or Houston because it wouldn’t be a good idea in Alaska, or something…

You get the picture. These people haven’t a clue about architecture, irrigation, plants, insects, birds, concrete, windage, logic, grammar… My suggestion to the OP of the thread is to delete asinine comments and Block dummies. That is what I do on my FB page. That way, thoughtful, informed, educated, progressive people could share reasonable information.