What could a tropical plant specialist possibly come up with that would accommodate a wall 200m long and 4 stories high, which faces North and is only a stone’s throw from the River Seine- lovely in the summer but with roaring winds in the winter? Well, I would imagine that many people asked that question of Patrick Blanc in 2005 when he began work on the vast Vertical Garden, Mur Végétal, part of the Musée du Quai Branly. I have watched Vertical Gardens on the telly, Gardener’s World Live did one in Birmingham one year, I think, and I have been less than impressed. Plants hanging from pockets in a jumble accompanied by over-enthusiastic voice-overs. Ouch.
But Patrick Blanc is the real deal. Take a look at the richness and density of the planting below.
Now, this is February, on a cold and grey day, so just like our own gardens, it would be churlish to expect a vertical wall to look totally fabulous, so there are some bare patches, see below.
and here, a plant that you would not expect,
There are many more brilliant photos on his own site which give much more detail than I could achieve. But I can tell you that we stood outside, walking up and down on the little traffic island in the centre of 4 lanes of traffic, looking at it, talking about it, photographing it, identifying plants or trying to, for about 20 minutes. He is very clear about his technique for planting, and, in case you want to give it a go, I have quoted it here…
“…On a load-bearing wall or structure is placed a metal frame that supports a PVC plate 10 millimetres (0.39 in) thick, on which are stapled two layers of polyamide felt each 3 millimetres (0.12 in) thick. These layers mimic cliff-growing mosses and support the roots of many plants. A network of pipes controlled by valves provides a nutrient solution containing dissolved minerals needed for plant growth. The felt is soaked by capillary action with this nutrient solution, which flows down the wall by gravity. The roots of the plants take up the nutrients they need, and excess water is collected at the bottom of the wall by a gutter, before being re-injected into the network of pipes: the system works in a closed circuit. Plants are chosen for their ability to grow on this type of environment and depending on available light…”
It is top-notch technical as you can see, and nothing is left to chance except for the effects of the elements in the case of an outside wall.
But, here in Tostat, and I really wasn’t sure about this, Andy took 4 baby agaves and posted them into the wall of our New Garden. No closed system technology for us, just some compost and the experience of someone who said that they had tried it. After the driest summer we have had in 11 years, they are still there, battered but unbowed. Here they are as they were in late Spring last year. The theory is that they are facing South for warmth, tick, and they will absorb humidity through the leaves without needing water at the roots, though we did water occasionally last year. So, when they make it through this soaking wet weather we are having, I will be eating hats.