So says Professor Dixon Despommier of Columbia University USA who is world renowned for his concept of the urban vertical farm - a high rise building of thirty floors or more with a footprint of five acres. His city situated behemoth of glass, steel, salads and chickens, would use aquaponics and aeroponics - processes of growing plants without soil. In order to feed a city like New York and you’d need 150 of these buildings to feed that city.
|Despommier with some food he grew earlier in that tower behind him|
|Balle's Dragon Fly Farm for New York - I don't think this one will fly somehow|
For this reason, most of their living walls will fail - by producing stunted plants with diseases. Onions and carrots can’t grow in the same homogenous upended giant seed tray. Amateur food growers know what architects and designers of novelty wall mounted growing systems don’t - you can’t bung a bunch of onions, tomatoes and chillies into one great big tight knit vertical patchwork quilt and expect to walk back to perpendicular cornucopia.
|A dead living wall in London's Islington|
I’ve just taken delivery of a massive 16 foot by ten foot and eight foot high shed which has robbed me of about a third of my total garden growing space. There’s a big chunky rain gutter on the front side which takes all the rain water from the roof to the side of the shed, down a drainpipe to the side.
My brainstorm involves bunging up the hole to the downpipe, filling the gutter with soil and growing lettyce in it. If my roof gutter can grow weeds and small trees, then why can’t my shed gutter grow rocket and mustard? The rain would therefore trickle down to give the salad a drink. So hey presto let’s tell the architects!!
|A lettuce gutter yesterday - looks like someone's beaten me to it!|
But with my greatly reduced backyard, I’m now facing the conundrum that many city dwellers face when trying to grow a bit of produce - a tight ground area and lots of upright vertical space crying out for an idea.
So this is what I’m actually going to do.
First, tomatoes - the best crop ever for growing up (or down) walls. They don’t require a massive rootball and can be trimmed, trained, wired or strung in all directions - best of all - upwards. Next up strawberries. I have loads of strawberry plants sitting around in window boxes and buckets which are set to make their big splash around May.
These I plan to suspend in a hanging gro-bag formation from at least one wall of either the shed or the house. Strawberries flower, fruit and then get in the way for the rest of the year. So the removable gro-bags will allow me to shift them into the dark side passage once the fruit goes and they start firing out those annoying runners.
Next, the grapevine. I have one in the corner of the patio but unfortunately the tomatoes shade it out. This will henceforth be situated at the sunny corner of this new shed, and will be trained out along the shed gutter thus turning it into a far more practical and productive aid to the larder than filling it with lettuces.
|They're grape for climbing - a vine scales a shed|
Next will be two shed hugging cucumber plants. These won’t be allowed out of the greenhouse until May or they’ll die in the weather, but I do have two or three salvaged and still loving rose bush stumps and rootballs in plastic bags and these will also be trained on the shed for colour but also for support - for the cucumbers. Once fed properly and provided with something to climb cucumbers will quickly swarm up a (sunny) wall and are highly productive. We don’t eat a lot of cucumbers so there will only be two.
Finally - last but not least I’ll be planting a damson tree that’s been sat dormant in a bucket on the patio since I purchased it in the autumn. Although it’s a tree with root capacity to undermine my shed foundations, I’ll be confining it to a big container and then training it along a wall with wire - making its branches perpendicular to the trunk in a well tested style which will yield buckets of fruit.
Small fruit trees are perfect along walls - they can be grown as high as you want and then cut off top and trained outwards. Try the container viable Irish bred Coronet mini apple tree which stays at four or five feet or try to find a small pear strain. Always beware though of the capacity of tree roots to do damage to walls though.
|An esplanaded pear tree against a wall|