by Bernadell Larson,
HCMG |
The Vertical Garden,
from nature to cities
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Patric Blanc is
considered the Father of
Vertical Gardens (also
referred to as Living
Walls). We have
permission to reprint
part of his article
describing a Vertical
Garden. |
Do plants really need soil?
No, they don't. The soil
is merely nothing more
than a mechanical
support. Only
water and the many
minerals dissolved in it
are essential to plants,
together with light and
carbon dioxide to
conduct photosynthesis.
Whenever roots are allowed
to grow deep inside a
wall, they can easily
damage the wall and
cause its destruction.
That is precisely what
happened to the Angkor
temples.
This root related damage
can be prevented if
water is regularly given
to plants.
 Roots
are then only spreading
on the surface, leaving
the inner wall
unaffected. From these
observations, and aiming
at setting up permanent
plant cover on walls
with a minimum of
maintenance, Patrick
Blanc conceived the
Vertical Garden. The
core innovation is to
use the roots’ ability
to grow not only on a
volume (of soil, of
water, of sand, etc.)
but also on a surface.
Without any soil, the
plant-supporting system
is very light and thus
can be implemented on
any wall, whatever its
size. The whole weight
of the Vertical Garden,
including plants and
metal frame, is lower
than 30 kg per square
meter.
Created by Flora Grubb
Gardens in San Francisco |
|
The Vertical Garden is
composed of three parts:
a metal frame, a PVC
layer and a layer of
felt. The metal frame is
hung on a wall or can be
self-standing. It
provides an air layer
acting as a very
efficient
 thermic
and phonic isolation
system. A 1 cm.-thick
PVC sheet is riveted to
the metal frame. This
layer brings rigidity to
the whole structure and
makes it waterproof. A
felt layer, made of
polyamide, is stapled on
the PVC. This felt is
rot proof and its high
capillarity allows a
homogeneous water
distribution. The
roots grow on this felt.
Plants are installed on
this felt layer as
seeds, cuttings or
already grown plants.
The density is about
thirty plants per square
meter. The watering is
provided from the top.
Tap water must be
supplemented with
nutrients. Watering and
fertilization are
automated.
Residential Shade Wall
. . . walls and plants, a
surprising, though
long-lasting combination |
The
Vertical Garden allows
man to re-create a
living system very
similar to natural
environments. It’s a way
to add nature to places
where man once removed
it. Thanks to botanical
knowledge, it's possible
to display
natural-looking plant
landscapes even though
they are man-made.
Besides, thanks to its
thermic isolation effect
(heat sink), the
Vertical Garden is very
efficient and aids in
lowering energy
consumption, both in
winter (by protecting
the building from the
cold) and in summer (by
providing a natural
cooling system). The
Vertical Garden is also
an efficient way to
clean up the air. In
addition to leaves and
their well-known
air-improving effect,
the roots and all the
micro-organisms related
to them are acting as a
wide air-cleaning
surface with the highest
weight to size
efficiency. On the felt,
polluting particles are
taken in from the air
and are slowly
decomposed and
mineralized before
ending up as plant
fertilizer. The Vertical
Garden is thus an
efficient tool for air
and water remediation
wherever flat surfaces
are already extensively
used for human
activities.
The
Vertical Garden on
concrete walls . . . A
shelter for
biodiversity
and a cleaning system
for cities |
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