Sunday, 1 July 2018

urban greenvasion: green gutters

Gutter gardens are typically evanescent items; adventurous weeds today, washed away tomorrow. Nevertheless I am a fan. They have a hectic enthusiasm, little scatters of the wild growing up out of our urban environment practicalities.

Gutter garden drainage kerb gardens
little tiny tree drainage kerb gardens

But would it be possible to design in these awkward little threads of green?

This is a concealed drain in my local mall which is open-style; rain and weather blows in, and needs to be shifted from the hardstanding. A slight slope in the paved area draws water down into the central runnel (the dark streak dead centre) from where it is whisked off into the local drainage system and away. So far, so bare. Now let's look at how the drainage runnel is doing just outside the roofed area, near a decorative garden:

You'll notice a built-up, almost what one might call a substrate, blocking the runnel, made of particulates, dust, plant debris, leftover building materials (a list to make our hardy urban plantset rootdrool) and the first moment it rains I rather think that this might happen:

Of course, this is the rough and ready sort of greenvasion. The first proper hard rain will wash those tiny seedlings away. But with a little planning, could we make our green gutters more structured, more considered, more permanent?

Here very roughly is how our concealed drain is working. Slowing down that wash-away might bring other benefits, too - cooling the area, reducing run-off. Let's work on that.

Here a grill has been added, containing hard-wearing plants. Hydroponic plus, they grow in debris with roots dipped in water. The little green grid creates a pedestrian speedbump that slows traffic and creates a natural milling-spot just outside the social (a convivial cafe-space). The gap halfway up is a throughbridge for wheeled traffic like wheelchair users, pushchairs and service vehicles, but it's expected and understood that this will be trodden on. Plants will live and die in this space. Lots will never make it past seedling, and anything too big will need to be weeded out in any case.

My original conception, above, retains more of an air of mystery, of green bubbling up through the cracks in a pavement (more on pavements is coming soon!). This one would suffer less from evaporation, but would be harder to maintain -- it might require easily liftable blocks. I think it might be worth it though, especially in areas like walkways and balconies.

The raw material greenery photo for my final design is worth a look, as it is the original design inspiration, and always in my mind when I'm thinking green gutters. This drain has long since fallen to the winds and waves of urban improvement, but in its day it was downstream from a coffee van, and a regular recipient of water, ice etc. dropped off the van at the end of the day, and occasional flushes of coffee grounds when something went wrong. The plants grew in it with tiny abandon, delighted with their little garden spaces:

reclaim the street

So, they obviously exist already, but are equally obviously evanescent, rather than year-round planting. They're also only ever accidental, never intentional.

Towards intentionality

Building in spaces for the weeds may be the easiest way to green cities. There's no expensive planting to coddle and manage; watering takes care of itself (or doesn't, during droughts); and bad weeding out the saplings, maintenance is low.

But to the urbanite's eye this communicates messy, tatty, urban decay. To the building services manager, it is roots to clog and prise and tweeze and penetrate. To the street cleaning crew, it's a job for the pressure washer and the hoe.

If these are to stay they are going to need to communicate intentionality, effectively.


So what do we need, to get from here to there?

  • Pre-moulded building parts made of durable materials with space for gunk and green to gather, but enough drainage not to cause puddles
  • A list of safe and unsafe plants, according to which have roots inclined to penetrate and damage, and which can be safely relied up on to matt (green roofs should have this, and more on them later)
  • A shift in attitude to see the volunteer greenery within an area as part of the building assets rather than a litter problem to be cleared (perhaps lead by identification posters, or ones that give statistics about drainage and cooling)
  • A better knowledge of our urban plant habitat, and an understanding of the species web we can support withing the urban environment (perhaps a book called Flowers of the Urban and Built Environment)
  • Someone to build this idea into a striking new town centre scheme.

Wednesday, 27 June 2018

urban greenvasion: insect elevators

Insects live in litter. Flies cluster round bins, beetles scuttle out from discarded wood, woodlice from under dead leaves. In the city, litter is tidied, or we get the worst of this; maggots, and all the other heralds of filth and rot.

Nevertheless, the lack of insects is a serious problem, and the bugs need space to live in; and in an urban space, where everything is determined by ownership and tenancy, this space should be designated. And given that most of our most beneficial, hardworking and attractive insects (it's an urban space, so I'm going to be picky!) are fliers, these spaces need to be primarily vertical.

Hence insect elevators, to let the butterflies and bees scale the sides of our desolate urban cliff faces in easy flutters, short buzzes.

Insect elevators operate to support invertebrates of all sizes to navigate from greenery at street level up to the different levels of the urban environment. While smaller and flying insects are delivered to all levels by wind, the turbulence around buildings is a challenging navigation environment for large winged insects like butterflies. Elevators give them a safer, sheltered route with multiple stop points -- think service stations or coffee shops. Linked by drainage pipes and trailing plants (as shown in my rather garish diagram above, even non-flying, short hop and heavier insects can successfully scale the wide expanses of bleak brick.

Do they exist already?

Pretty much, though they're not called this. Of the various types of elevator available to municipal design, the most striking, impressive (and expensive!) is the green wall, but cheaper options involving creepers, window boxes and cornice planting are also options which may be both cheaper and more congruent with the traditional urban environment.

None of these are, strictly speaking, however, intentional insect elevators. Their elevatory aspect is accidental, a byproduct of their main aim which is to please the human eye. They are intended to beautify the urban environment; any environmental improvement, any provision of habitat is a happy accident. A byproduct. As such, insect invasions may be resisted, plant selection may not be suitable, and wherever a corner needs to be cut, they will be dropped, and the crisp, dry, clean insect-unfriendly but easy to maintain spaces will return.

Insect first design

Am intentional insect elevator puts habitat first. Soil biome, micro environment and linkage (we'll return to green chaining in a future post) are all more important than aesthetic appeal. The design leads from what insects need.

That said, human convenience matters. The item exists within the humaniform space, urbanity or suburbanity. It must be maintainable and safe; it must not seem too untidy, or stick out, like a nail that needs banging in. It can operate as a statement that can be enjoyed or objected to, or as a lightweight, interstitial item that eyes skitter over. But it must never look like litter, mess, chaos, or urban decay.

My startling, angled pots in the picture above nod to that. It's making a statement which is only partly green. Humans pay money, after all, to look at butterflies and keep bees. This is product, and urban space is at a premium. It must sell.


So, what do we need, to get from here to there?
  • Cheap to fabricate boxes, with insect habitats and linkages built into the initial design;
  • Resilient planting that can establish successful biome in a tiny space;
  • Preseeding with plants and insects, perhaps in a staging nursery/insectory area at ground level;
  • Maintenance at height, perhaps through a combination of long-pole watering and less frequent maintenance through roped climbers (you see both these in window cleaning at the moment); and finally:
  • Greenery at both street level and at roof levels.
And we'll come to those in a future post.

urban greenvasion

As the temperature rises, plants ooze up from every crack and crevice, shoot out of clagged gutters and cracked chimney stacks. The urban greenvasion is underway.

hopeful seedlings

But these isolated dots of green are insufficient for the needs of the city. There isn't enough to support even the simplest of ecostystems; insects limp from scrap to scrap, like sea-weary sailors seeking an island large enough to live on. Vast deserts of grey and dun and dust and dryness separate everything. Nothing links, so everything is only passing through. Most plants that try these spaces die in the dry. Nothing can permanently live here.

Erigeron, self-palnted

What could turn this around? What could permanently and sustainably green our cities? Over the next few posts I'm going to explore some ideas, big and small, about how to consolidate the summer greenwave into something more long-term; a way to transform our vagrants and invaders and green litter into a force for urban good.

crack garden

Sunday, 24 June 2018

dancing on the natural history museum ceiling

I suppose that theoretically a person could lie down on the floor in the Hintze Hall of the Natural History Museum and just stare through the pale bones of the massive blue whale at its amazing botanical painted roof for as long as you wanted, surrounded by tiny children and anxious museum attendants, but

Unless of course, you've been given a rug and told to find a place:

dinosnores settle in

So here we are at Dinosnores for grownups, somewhere in between a lecture on parasitic wasps, the insect tasting and prosecco.

dinosnores settle in

and all I can do is look at ceiling!

dinosnores settle in dinosnores settle in
dinosnores settle in dinosnores settle in

Famously, the pictures are all accurate botanical illustrations; the animals are real animals, the plants real plants, plants that are of use to humans, rendered in the respectfully utilitarian style of high Victorian instruction; here are the plants, and this is why they matter, and here is a pretty border around the edge, because they deserve it:

dinosnores settle in

Wednesday, 20 June 2018

volunteers and vagrants

I took one green recycling bag of couch grass roots to the tip (these belong to previous run of garden waste recycling and are no longer collected from kerbside, but I kept the bags because they are great for weeding, trimming etc.) and it was so heavy I nearly herniated the helpful man who saw me struggling and came over to help. It's all one plant, technically speaking, a root-spread clone.

In among the couch grass mat are the fragments of the last occupant, like exotic vagrants in a flock of starlings. Here's a yellow chard:

Allotment progress

Most striking of all are the sprouts of last year's potatoes. So far I've found ten or twelve plants. Apparently they're called volunteers, and I can eat them, if they make anything worthwhile.

Other treats and delights include many, many paving stones, masses of bricks and a big old tarp:

Allotment progress Allotment progress

Currently supressing weeds and spreading ants nests. I have a lot of ants. But to return to the couch grass, taking it all to the tip feels inappropriate, plus I lost a quantity of topsoil doing it. Time to activate one of the weird composting solutions. After all, I did inherit a suitable trug:

Allotment progress

Click through to Flickr for context notes and more photos.

Friday, 15 June 2018

Boring Flowers

Lured back by the thrill of the mundane, we went to Boring again this year. I took a moment in the afternoon to eat an ice lolly and check out the flowers in Red Lion Square, which last year had been very striking and included a fully in-flower Judas Tree.

This year, things were a little more, well, boring:

Yellow tulips Yellow tulips Yellow tulips
Yellow tulips Yellow tulips Yellow tulips
Yellow tulips Yellow tulips Yellow tulips

Plain yellow and red are the basic bitches of the tulip world, so initially I was unimpressed. But something about their irrepressibly sunny faces, battered as they were by this year's uneven weather, won me. The plain colour forces a Warhollian focus on outline and colour block. Perspective and depth collapses into pigment overload, like an award-winning YBA reinterpretation of the traditional portrait. Each billow and notch of the petal chops into negative space like Matisse cut-outs.

As for the plants, they had a slightly unstable air, as if they'd been brought in as reserve after the main flower set had failed; a hypothesis supported by the large tracts of bare earth and the occasional collapsed plant where they had not taken.

Yellow tulips

Thursday, 14 June 2018

first fruits from the allotment

Mostly, it all got eaten by slugs. But here and there, a hardy survivor. I ate this -- despite being rather underwatered and undersized, it was a proper peppery radish mouthful.

Implausibly, the strawberries had also made fruit - despite there being no earth to earth them, no watering visits and no straw to keep them cosy.  Alas, my dreams of these being less bothered by slugs were just that; dreams. The most-promising looking strawb was hollow when I turned it over. This one wasn't though; I had a small handful of strawberries.

The broad beans were short, but setting pods already (and collecting the usual little halos of blackfly). I have about seven parsnip plants. The potatoes are putting on growth, although the fact that one's flowering already is a bit of a cross-sign.

Clearing a bed for beans I found more potatoes, leftovers from last year, strangled among the couch grass. I freed them out but there was a weird amount of red ant activity, including some in some large, leftover potatoes. Gardeners world is very firm on this: ants do not eat potatoes. But there are hints elsewhere that this can happen.

I gave everything a good water and left it to it. I'll see if I can wiggle up some little potatoes next time I'm up there, and maybe I'll lift that onion, too.