Category: landscapes

March 24th, 2020 by Mark Laurence

This is the third in a four-part series. In previous articles (links at bottom) I talked about the spontaneous regeneration on brownfield sites in the UAE and the utilisation of seeded landscapes to create semi-natural ecosystems without irrigation. Another factor of these landscapes would be to make them productive in a way that would enrich the soils of not just that landscape but, by the production of useful products, returning fertility to the soil for both the site concerned and also urban landscapes and gardens elsewhere.

Sesbania sesban, a nitrogen-fixing shrub or small tree

Coppice woodland is not a term that you normally associate with the Middle East, yet there are many trees, both native and introduced, that would work in this manner. So what would be the point? Well, we have become used to landscapes being either for agriculture, or for ornament, yet this simplification overlooks the fact that we can have landscapes that are multi-functional and that they can also be productive in other ways.

To understand this concept, we should look to agroforestry, or forest gardens, where multi-functionalism is the order of the day. We think of these systems as being in tropical or temperate regions, yet there are many plants that can be organised and used in this fashion in arid lands. I want to focus this article on one aspect only, the production of biomass. Biomass has multiple functions: the production of poles for building and firewood, compost, and when shredded, mulch. We can produce biochar, which is seen as an increasingly important part of long-term soil enrichment and carbon sequestration. There are also food and fodder crops which would be a valuable product, dependent upon species. And of course, verdant biomass supports verdant wildlife.

Eucalyptus street tree, Abu Dhabi. Note the epicormic growth from the base

Many of these plants are also nitrogen-fixers and these are especially valuable for building fertility and assisting the development of other species. Whilst some may have allelopathic properties, which inhibit the germination of other seedlings within the root zone, my general observation is that this is not particularly effective, nor a problem.

So a list of trees that would grow in the Middle East unirrigated, can be coppiced and are nitrogen fixers, would include:

  • Acacia saligna
  • Acacia (Senegalia) senegal
  • Acacia tortilis
  • Albizia lebbeck
  • Leucaena leucocephala
  • Pithocellobium dulce
  • Prosopis cineraria (possibly)
  • Prosopis juliflora
  • Sesbania sesban
Strong epicormic growth is ideal for coppice. Prosopis juliflora

Other species, coppicable but non-nitrogen fixing, would include:

  • Azadirachta indica (assumed from observed regrowth)
  • Conocarpus lancifolius (assumed from observed regrowth)
  • Eucalyptus sp.
  • Ficus sp.
  • Moringa oleifera
  • Tamarix sp.
  • Ziziphus spina-christi
Ziziphus spina-christi, showing classic epicormic growth

There will be many other species that could fit these lists, but it’s a start. Many ornamental trees, such as Millingtonia and even Delonix show tendencies to throw up epicormic growth from wounds and therefore, in theory might coppice, but I am concentrating on trees which can do this without irrigation.

It’s important to say right here that this shouldn’t ever be designed as a monoculture; there is sound ecological reasons to to maximise the diversity of a planting. Naturally, you wouldn’t use everything, for conditions will suit some better than others for any given site. Nor would you coppice everything all at the same time. Staggering the harvest evens out the work-flow but more importantly, creates communities of plants at different stages of growth. The “edge zones” are always where the greatest biodiversity occurs, for you get the overlap of differing ecologies. Whilst each species will have it’s own regrowth rate and optimum cutting cycle, this can also be varied, according to the use of the product.

Of course, there is a problem, for many of these species are incredibly thorny, which is a real issue for those carrying out the coppice-work. Young vigorous growth also tends to have the most vicious thorns! On a larger scale, it may be possible to use forestry-style Forwarder tractor-trailer units to collect the brush and load it directly into the chipping machine hopper, without human intervention. Someone’s still got to cut it and do initial handling though.

Ziziphus stump, showing strong epicormic regrowth

So how do we express this idea, of coppiced woodlands, arid-land style? it would depend on context but there are several approaches we could take. On a large scale, machine operated (as mentioned above), we would have to do traditional layouts with alleys or rows, firebreaks etc. Mixed planting though, would be preferable although strips of one species are possible. If kept narrow, with different species to either side, the effect ecologically would be similar to mixed planting.

In smaller areas, or where human interaction is intended, then these could take the form of the mixed, seeded landscapes that I discussed in my previous article. In other words, we can combine the function with the elements of aesthetics and ecological diversity. Not to mention desert reclamation. Remember, all this is proposed as unirrigated land. The verges along main roads are a prime candidate, instead of over-manicured lawns and hedges that you see at many junctions.

My next article will discuss design, the knowledge and training needed for the creation of such landscapes. I believe we could transform the landscapes of the Middle East, without the intensive irrigation that is required by conventional approach.


First and second articles in this series:

Posted in Abu Dhabi, Adaptive Planting, Agroforestry, Brownfield regeneration, Climate Change, Coppice, Ecosystem Services, Environment, landscapes, Middle-East, Natural Landscapes, Regenerative Planting, Sustainability, Trees, Treescapes, Uncategorized, woodland Tagged with: , , , , , , , , , ,

March 13th, 2020 by Mark Laurence

In part one of this four-part series, I discussed the colonization of brownfield sites in the UAE’s cities with a range of trees and shrubs – almost all of them “exotic invasive” species.  I argued that these could be forming the basis of new, adapted ecologies.  To revise those arguments, please the link at the end of this article.  The next question is, once we accept this premise, how do we create these new ecologies as a conscious expression of our own adaptation to climate change?

A self-seeded landscape, Abu Dhabi

First, let’s understand that we need these landscapes to be unirrigated.  Why? Well, in the Middle East especially, water is a precious resource and expensive; the UAE is particularly bad, with a per capita use of 550 litres/day.  So with landscaping, let’s keep the irrigation for the urban centres, parks and gardens.  If we just focused, for example, on all the miles of roads and interchanges between Dubai, Abu Dhabi and Al Ain that are irrigated, and imagine these replaced with unirrigated greenery, the water saving from this alone would be massive.  Yet that is an immense challenge, for as soon as you plant something in a desert, you must water it.

If we want a vibrant plant ecology, then we also need a vibrant soil ecology, something that conventional landscaping ignores completely

I think this is the key, that planting in such a climate rarely establishes without help, whereas seeds can.  What we need therefore, is a methodology of establishing and maintaining, seeded landscapes.

Flowers of Prosopis juliflora attracts bees and insects

It is true that in a scenario where we are consciously creating an unirrigated landscape, we would want to greatly increase the odds of establishment.  In this respect, much detailed assessment would need to be given to soil amelioration.  If we want a vibrant plant ecology, then we also need a vibrant soil ecology; this is crucial and something that conventional landscaping ignores completely.

Can we create a healthy soil, rich with microbial activity and naturally water retentive in such an arid climate?  I think we can, but we must first change our thinking from one of assisting landscapes with external inputs (irrigation) to that of creating self-sufficient ones, with cyclical, living, self-sustaining ecologies. Soil becomes the vital kingpin in all this, not just an anchorage medium for plants. 

Native soils need to be worked with, not replaced.  They can be moderated, made more moisture retaining, but basics like salinity and pH will always dictate plant choice.  First and most important, is to increase the soil’s water retention capacity. There are a number of ways to do this, involving additives which may incorporate clays, granules or other water-holding mediums and we know that when used in irrigated landscapes, they can reduce water demand by up to 50%. Given that an unirrigated landscape might have periods of time when it is extremely dry, we need a medium that doesn’t become hydrophobic if it does dry out and that will react swiftly to absorb water when it does arrive.

Sesbania sesban, a nitrogen-fixing shrub

We can also inoculate the soil with mycorrhizal fungi cultured from local, healthy environments to enhance soil micro-ecology; there is little point in importing this from another part of the world, as the relevant strains of microbes are likely absent.  Microbes and bacteria are the essence of good soil. Many of the plants used will be nitrogen-fixers, and so live in a symbiosis with certain bacteria. They also make nitrogen available to other species, as cycles of life and decay build up.

Organic matter is also essential, but perhaps the most problematic element as it is in short supply. One aspect of the practical usage of such landscapes, and a part of the long-term management, can be the coppicing of trees and shrubs for biomass to make compost. Organic matter tends to oxidise if conditions are not conducive, so we need to get things right, but I’m sure that even desert soils can sequester carbon, given the right conditions.

We would need to mix these various elements into the soil to the appropriate depth, perhaps a metre, probably by air injection, and possibly to different depths for the different mediums. Soil preparation becomes the most major, one-time investment in the land but will pay back endlessly over the lifetime of the landscape.

Black Carpenter bees on Leucaena leucocephala

Once the preparation is done we have to seed the land, when conditions are optimal (not when contract deadlines require); this would have to be timed after rain, if possible.  Otherwise, I would give the land a soaking, with our soil amendments helping to retain the moisture, then apply seed, in a variety of ways, possibly by hydra-seeding.  Finally, a locally-sourced stone mulch should be placed over all, to again help retain moisture, but not too thick to inhibit germination.  This would be the entirety of the preparation and installation work. 

Next is the nurturing stage, followed by on-going management and maintenance; this will be very different from a conventional landscape, but no less intensive, at least for the first few years. It may be beneficial to give additional watering to aid plants as they germinate and establish, but this must be done with care, or seedlings could be washed away. We would need to give enough to ensure success, but no more.

Once established, these plants would grow at whatever speed the conditions allowed and a new landscape would emerge over time. Thinning out and reseeding of failed areas would be the main work, acts of stewardship rather than maintenance. Prunings shredded and spread as mulch, soils fit to support life, insects, animals and birds would soon make this place their home. The result would be a slow and genuine landscape uplift into the realms of a new and adapted ecology.


How we design such landscapes, choose which plants to use, obtain the seed and know how to maintain them, is the subject of the next article.

The first article of this four part series is:

Posted in Abu Dhabi, Adaptive Planting, Brownfield regeneration, Climate Change, Dry Garden, Dubai, UAE, Landscape Futurism, landscapes, Middle-East, Natural Landscapes, Planting Design, Regenerative Planting, Sustainability, Trees Tagged with: , , , , , , , , , , ,

Natural regeneration on a brownfield site Dubai
March 8th, 2020 by Mark Laurence

This is the first of a four-part article, links to the others are at the end.

These articles are all a part of the same thought progress, which has been brewing for some time and started with an article I wrote two years ago, in March 2018.  I think this is an important subject, and hope that you’ll agree and read them…

Whenever I am in the UAE, I find time to visit various parks and gardens; on my latest trip to Dubai (February 2020), I went to see Al Ittihad park, a well-kept secret in the spine of the Palm Jumeirah, underneath the monorail, which was designed using native and naturalized plants of the UAE.  It also, the blurb said, promised everything was labeled, so ideal for a crash course in local flora.  The park was interesting but unfortunately all the labels had gone, and it was being maintained in the manner of all landscapes; incorrectly, especially so for native planting.

Of equal or greater value, however, are simple walks around the back-streets and suburbs of a city and I find empty brownfield sites, awaiting development, often offer the best insights as to what will actually grow in an arid region, if things are left to their own devices.  It’s more than you’d think, and it’s not all native.  I’ve written about this before, in this article and I’m building here on my earlier observations.

Video of brownfiled site in Dubai showing natural regeneration

The world is gripped in fear of biological invasion, currently of Coronovirus but I’m talking here of the floral kind.  Globally, there is a growing passion for conservation, restoration of what was, of what we think of as native and right.  We seem to think that in taking this approach, we are setting right the wrongs we have done; nothing could be further from the truth. Fortunately, Nature doesn’t share that passion and is busy dispersing its flora and fauna around the place, wherever and however it can.  That it uses humans as vectors for that dispersal, is obvious, if you just look upon it from a wider perspective.  Perhaps Nature knows something that we humans are trying hard to ignore; that the climate is changing, the rules of life are shifting, that ecologies need to adapt to the new conditions. 

Leucaena leucocephala

I think we humans are both arrogant and ignorant when we say, “that plant doesn’t belong here, we must get rid of it”.  Plants that arrive and succeed are the pioneers of a new, adapting ecology; yes, they are aggressive, yes, they grow without restraint and colonize -usually – disturbed ground, yes, some make monocultures.  Like all pioneer species they are fast, competitive and relatively short-lived.  But they establish life and the conditions for the next species of successional plants to come along.  All parts of the world are, or soon will be, under such huge environmental stress that we must actively embrace change and nurture these new ecologies. We cannot live in a world without complex ecology, nor can we hold back the change, so we have to go with it.

Prosopis juliflora

To come back to my brownfield sites, on my previous article, linked above, I encountered the following trees growing on a brownfield site in Abu Dhabi:

  • Prosopis juliflora
  • Ficus benghalensis
  • Eucalyptus camaldulensis
  • Conocarpus lancifolius
  • Washingtonia robusta

From recent observations in Dubai I can add the following trees:

  • Azadirachta indica
  • Leucaena leucocephala
  • Plus the Prosopis and Ficus from the above list.
Azadirachta indica

From the looks of it, this site was more recently cleared than the Abu Dhabi one, and trees appeared to be no more than 2-3 years old.

There were also a range of groundcovers and grasses growing; I haven’t been able to ID them all, but some I saw included:

  • Aizoon canariense
  • Heliotropium bacciferum
  • Salsola collina
  • Tribulus terrestris
  • Chloris virgata
  • Panicum turgidum
Tribulus terrestris

Such plants are equally important in building new ecologies, and a big part of the whole.  There are of course, a huge range of native or adaptive plants not represented here, which would nonetheless grow, given the chance.

These observations might be interesting, but how useful are they? If we think of conventional, irrigated landscapes, perhaps not very useful at all; we know and use many of the trees already.  Where this becomes interesting, is in that they self-seed and establish without any human intervention.  If we could master the art of this, then such landscapes we would nurture and manage, with occasional thinning, removals, perhaps some sucessional seeding or planting. Imagine this on a large scale, in peri-urban locations, alongside roads, at intersections, instead of the over-watered ornamentation we see now throughout the UAE.  We then save the ornate for the urban parks, streets and gardens.

Aizoon canariense

Could this be the basis for a new approach to creating landscapes and if so, how would we do it?

This is the subject of the next article:

Posted in Abu Dhabi, Adaptive Planting, Brownfield regeneration, Climate Change, Dubai, UAE, Environment, landscapes, Middle-East, Natural Landscapes, Regenerative Planting, Sustainability, Trees, Treescapes Tagged with: , , , , , , , , , , ,

Mark Laurence's gravel garden
February 2nd, 2020 by Mark Laurence

Gravel gardens have been around a long time yet with a few well-known exceptions (Denmans, Beth Chatto and more recently, Olivier Filippi), never really make it into the mainstream of garden design. I suspect that for some designers, there is insufficient structure to satisfy, yet that is actually one of the main benefits. This makes them low-impact, from a carbon perspective, and naturally adaptive, with the kind of planting they use.

I have been designing such gardens for the past twenty plus years, and a part of my own garden is gravel, on the area of an old driveway; it’s the part I enjoy the most. Unlike perennial borders, there is structure all year round and I often wander around in the depths of winter, enjoying the shapes and forms, or the scent of rosemary (sorry to say, now officially Salvia). It’s like you’ve brought a little bit of the Mediterranean into the garden. Plants self-seed around and it’s always a bit different every year. It’s a style also eminently suitable for the arid regions of the Middle-East, whether xeriscaped, or not.

Not everywhere is suitable for a gravel garden and the obvious criteria of sun exposure and poor(ish), free-draining soil are a must. Whilst drainage and soil structure can be altered, aspect cannot. The other factor, frost/cold exposure is actually not such a barrier, although it will limit the plant choice a bit.

A part of the design of the gravel garden described below

Some years ago I was tasked with turning an old farmyard on the South coast of England into such a garden. The compacted rubble was on average 50cm deep, so we loosened and/or removed about 400 tons and replaced a similar amount of topsoil into slightly contoured mounds. As it was a farm, the soil was already available stacked on site and there was somewhere to remove the rubble to. We then rotovated 50cm of gravel into the mounded soil to improve drainage and planted with a range of “Mediterranean” plants. Most were from this region, with some Australian/New Zealand species, most notably Phormium (which I probably wouldn’t use today). We also built a stream and water feature, using 30 tons of boulders (glacial, so not strictly true to theme).

Adding 400 tons of soil
Rotovating in a thick layer of gravel

If I were doing this today, I’d leave even more of the rubble in place and blind the soil in over it. Over time I have come to realise that such conditions are an advantage, and expected by many Mediterranean plants.

Placing boulders and a stream+pond

We used a drip irrigation system for the first year of establishment, which was then switched off in the second year. A 50mm deep dressing of 20mm diameter marine shingle covered everything, including the paths, which were left from the original, compacted sub-base.

Planting
After One year
After Two years
After Four years

I tracked this garden for a few years until the property changed hands and learnt some valuable lessons (as you always do), such as don’t put too many larger growing shrubs in, as the openness of the spatial structure becomes compromised. Whilst they are good at establishing initial structure, be prepared to remove some of them as the garden matures. Some, like the Cotinus and Tamarix, were meant to be coppiced every few years, but didn’t have this done. Some perennials work better than others and low mounding shrubs are what make the predominant visual structure of the site.

This last two pictures, plus the header, are a part of my own gravel garden, created over an old driveway, where I constantly experiment with new plants and slowly expand it all.

My gravel garden. Mounded foliage dominates the structural form

Gravel gardening has much to offer and is an appropriate approach for our time, being of low carbon footprint and using plants that are adaptive and generally tough. Have a go, or get me to help…!

Posted in Adaptive Planting, Biophilia, Climate Change, Design, Dry Garden, Environment, Garden Design, Landscape Futurism, landscapes, Middle-East, My Garden, Natural Landscapes, Planting Design, Sustainability Tagged with: , , , , , , , ,

January 28th, 2020 by Mark Laurence

If you work in the realm of landscapes, you cannot ignore the huge rise in the use of artificial plants, “green” walls and especially, grass. It’s a booming business and many companies are doing very well from it. But we should also be hearing warning bells ringing about how damaging these things are, both to the environment and to our individual well-being.

I’m concerned about this damage, mostly to our inner beings.  I wonder if we have become unable to comprehend that such things show our disconnection from the real.  I’ve worked with plants all my life and always my prime motive has been our connection to nature.  Now I design, write, think, talk; always my concern is for the environment and the well-being of the human spirit. This artificiality in landscape betrays both these things.

It is not enough to say this, so I must justify it, even though the obligation should really be the other way around; people who purvey such things should have to prove that they don’t cause ill-effects. But such is the state of human consciousness that commercial profit always comes before anything else.

This is not an article about the merits of grass as such, nor what we might use as natural substitutes; that topic has been written about many times. This is about what we do to ourselves when we surround ourselves with fakery – and I don’t mean in politics, although there are parallels, doubtless.

We constantly sell ourselves short on what it is we actually need, as individuals. This is me, an environmental designer, saying us humans should be selfish, and demand more. But not more in material terms, in things. More in Soul, in environmental harmony, in biophilic contact. More respect for the awesomeness of Nature. How can we substitute the reality of Nature with plastic, and tell ourselves it’s okay? This is self-deception on a massive scale, and we need to be aware of it, and reject it.

Before going further on the psychological front, let’s talk about the environment. Artificial plants are mostly made from plastic (although high end plants may be silk). Plastic is a one-way route to pollution and there is no difference between the plastic in a green or artificial grass and the plastic that’s floating around in our oceans. It’s the same stuff and will end up in landfill, being burnt or in the sea as microplastics, amongst its peers.

Grass comes in many forms, from tidy, to uncouth; the less couth, the better.

Artificial grass also is responsible for killing off the soil and its ecosystem in areas that once were living. Even (real) lawns are of environmental benefit, although other forms of landscape are preferable and yield higher benefits. Yet a lawn is alive, absorbs rainwater, has a life within of earthworms, larvae and micro-organisms, and stores a surprising amount of carbon. Artificial lawns do the inverse of all that and are not even as low maintenance as people think, requiring regular brushing and hosing. You must replace it every few years, too, with rubber crumb underlay being especially problematic to dispose of.

We buy into these products because we think we are being sold an easy life; in fact, we are being sold a deception, that Nature can be imitated, bettered. That you don’t have to get involved with it in any way, that the real thing offers nothing better, that biophilia (your innate need and love of Nature) can be mimicked. But your inner being is not deceived, just your outer one.

On the whole, we don’t realise just how disconnected we have become, in our modern societies. Each generation has less contact with natural systems and ecologies than the last, and each generation perceives its own experience of reality as normal, how things are.  If we could go back 100 years, I think we’d all be astounded at the verdancy and variety of life, of just how rich and varied Nature was.  Perhaps then we would wake up to the fact that we have forgotten our roots and lost our way. Now, we surround ourselves with the artificial and think that it is okay.

Landscape design doesn’t help in this respect, especially in the public realm.  Commercial space becomes dominated by hard materials; plants, where they exist, are regimented and ordered.  Water features are devoid of plants because they are messy, need skilled maintenance and the chemicals in the water wouldn’t support their growth anyway.  How sad, what an opportunity missed, what absence of life in our urban landscape.

In all our striving, we should remember above all where we came from.  A disconnected life allows not only the artificial to be okay, it switches off our concern from the environmental and climate crisis, as if we live in a bubble of man-made life, separate from the planet.

So for the sake of you own being, ditch the artificial.  Embrace the messiness and verdancy of Nature, get your hands dirty – the bacteria are good for your health and your happiness.  Let your children experience this, teach them about that wild and somewhat frightening side of Nature, for it needs our respect, and our love.  And if we love Nature, we might just find we can finally love ourselves.

Posted in Biophilia, Climate Change, design principles, Environment, landscapes, Natural Landscapes, Uncategorized, Urban Landscapes Tagged with: , , , , , ,

Trees add height and microclimate
December 9th, 2019 by Mark Laurence

Landscapes are all about creating micro-climate, or would be, if designed for that goal. Why is this important and what do I mean?

Almost all life is contained in a thin crust of soil, a wedge of atmospheric gases, and water. Plants are the principal medium that interacts with and regulates all three. Absolutely nothing else does this as well, or at all; think about it.

The way we organise our plants in our urban landscape will determine how well this interaction occurs, how successful it is. Yet I have never heard of a single project that has been developed with this understanding and this goal in mind. With climate change, we urgently need to re-think the way we design our landscapes, and why we design them. Whilst all the human-centric design reasons will always hold true, we need to layer into our thinking this new understanding of how plants interact. To build new ecologies, new ecosystems, we have to design for plants to actually function, rather than just look nice. For when they do this, our environment literally comes alive. More importantly, they might just, if done on sufficient scale, save us from ourselves.

When I use the word treescapes, I don’t just mean trees and grass; we’ve had that for years in the form of parks, and in their traditional form, they’ve done little for us. No, our designs need to build up layers of living material – biomass, for with biomass comes moisture entrapment, shade, food for insects, etc. Think of it in terms of height and depth of microclimate. How much depth is there in a stretch of irrigated grass, maybe 50mm above ground, 200mm below? No species variation, so what we have is little more than a green desert, albeit one that can hold bit a of moisture.

Trees in paved streets are also less able to generate micro-climate, but they are a bit of an exception, as they provide shade for people to walk under. Where width allows, even here we should layer our planting.

Trees in grass lose most of their microclimate
Trees in grass lose most of their microclimate and ecology. Traditional design fails us here.

If we replace that grass with a range of groundcover plants – not a monoculture – you begin to get a little more variation; different root structures and depth, different foliage shapes, height, form and flower. More variety, more microclimate, more food source, more ecology. Looks good too.

Next we add shrubs and suddenly we are into an new realm, that of woody plants (I’m being simplistic here, many groundcovers are of course woody). Shrubs create three-dimensional space with their frameworks, within which micro-worlds reside. Deciduous plants shed their leaves, as do evergreens, and this begins to build leaf litter – mulch. Don’t tidy it up! We need ecologies in that soil, and microbes need food. Our obsession with tidyness has a lot to answer for. Suddenly, we have height in our micro-climate, three-dimensional form. We humans (for we scale everything according to our own height and perception) can walk amongst these plants, take part, interact. Our microclimate is now two metres high, maybe more. But something is missing and it’s still too hot…

Here we have (in Umm al Emarat park, Abu Dhabi) the beginings of an true microclimate. This is a treescape.
Here we have (in Umm al Emarat park, Abu Dhabi) the beginings of a true microclimate. This is a treescape.

Trees! Now we have a game changer and our micro-environment just became vast, in relative terms, maybe up to 30 metres, though 10-20m may be more average. We now have true diversity of shape, height, leaf, flower and roots. We have shade! Under trees it may be 10°C cooler and we love it. Plants love it too. Moisture now gets retained within the human habitable zone, fungi and microbes thrive in soils, insects and birds abound. This is our urban jungle and we need it. The planet needs it. This tiny sliver of crust we live on can be rich, abundant, in every climate and every place, if we put our minds to it, if we have the will. And when the planet becomes searing, creating livable environments with trees of any type, may be the only thing that keeps us alive, unless we become troglodytes.


This is the next level of landscape design, the new challenge; creating future ecologies and environments that matter, that keep us cool, that give us resources and soothe our souls. We will create new (novel) ecologies that fit the changing environment, trans-migrating parts of ecologies that once lived elswhere. In that place they may be dying out, as might your local ecology. If they now fit where you live, that’s where they need to be. In turn, that place of origin may itself need to adapt and change. In all things and all places, we need microclimate, shade and soil.

Are you up for it? I am!

Posted in Adaptive Planting, Arboriculture, Biophilia, Climate Change, Design, design principles, Dubai, UAE, Ecosystem Services, Environment, Garden Design, Landscape Futurism, landscapes, Middle-East, Planting Design, Sustainability, Trees, Treescapes, Urban Landscapes Tagged with: , , , , , , , , , , ,

Adaptive landscape design
April 25th, 2019 by Mark Laurence

The world is finally, at the last minute, waking up to the impending effects and consequences of climate change. In the scramble to work out what we must do (apart from the obvious cessation of burning fossil fuels), one thing, one factor is looming large: we need to put carbon back into the soil, where it can be stored indefinitely, and we need to reforest the Earth. Much of this is in the agricultural realm but there is a huge amount that can – and must – be done within the landscape and horticultural sectors.


Horticulture has a MISSION, it just doesn’t realise it yet

At the centre of this is good soil husbandry, something that we have largely forgotten about. Modern agriculture bypasses all need of soil health by chemically feeding crops; no need for microbes, nutrients, humus, mycelium or earthworms. Chemical fertilisers and herbicides bypass the lot. Most of our soils now are depleted to the point of useless by chemical farming, exacerbated by the tradition of ploughing, which causes erosion from rain and enables much of the soil carbon to move back into the atmosphere.

So whilst we need current global models of food production to transform into regenerative agriculture and agroforestry, we also need to look at our urban landscapes and gardens, and create a new design ethic, a new paradigm, even. I can’t deal here with agriculture but I have been thinking long and hard on what the landscape and horticulture trades need to do; fortunately, I believe there is a lot that we can do.

We need to envelope our existing horticulture trade within ecology, to create an “environmental horticulture” You could also call it ecological, resilience or regenerative horticulture. We (those of us in the trade) know that as a profession, the training of both horticulture (growing) and landscape (doing) are in decline. Horticultural colleges have shrinking budgets and often get the less ambitious or capable students; after all, who is inspired by the prospect of strimming verges or hedge-trimming another unloved carparking lot? Yet last year’s report by the Ornamental Horticulture Roundtable Group valued horticulture at £24.2 billion in GDP in 2017. That’s not inconsequential, yet it goes unrecognised. Fortunately, there is a way to make it much more enticing to prospective students.

Horticulture has a MISSION, it just doesn’t realise it yet. That mission is to adapt our urban landscapes and gardens to cope with climate change, to mitigate temperatures, water flows, to grow biomass and regenerate soils back to health. Healthy soil is the foundation of life, of all life, including our own. Good soil holds fertility, water and carbon. Yet who amongst us now knows much of soil science? Who designs landscapes as ecologies, as “novel ecosystems”, who chooses plants because they have these abilities, not just for pretty flowers? Who designs plantings for their biomass harvest, for creating mulches to feed the soil?

In this respect, I don’t believe it’s necessary – or right, in fact – to work with native plants only. What is native? What was native? What was here 11,700 years ago when the last glacial period ended and the glaciers retreated? Flora and fauna move around the globe all the time, they are opportunistic, not fixed permanently into some tightly integrated ecosystem. We know there is no “ecological climax”, no ultimate ecosystem for any given place. As temperatures rise, climate zones are now shifting away from the equator quicker than Nature can keep up, although it’ll get there eventually. Maybe we help nature, rather than interfere when we bring in exotic plants that naturalise. Maybe those plants are the start of new ecologies that will adapt to the rapid changes that this climate emergency is bringing us. If plants do well, we need to understand how to enhance and build new ecologies with them. This is how we adapt, how we survive and how we rectify the damage we have done as a species; not by returning to some pristine “before” (which doesn’t exist) but by assisting Nature to heal and adapt. The Earth will do this all by itself, and has done so many times. It doesn’t mind if it takes thousands, or even hundreds of thousands of years to adapt. But we do; we can’t wait that long.

So horticulture needs to stop growing pansies in peat with unrecyclable plastic trays and start sorting out which plants really matter for our future; which ones contribute to new and existing ecologies, which ones are good for biomass, which ones contribute to soil health, which ones give us ecosystem services. We should not enhance one environment at the expense of another.

What’s needed is a very-near future profession of trained eco-warriors, soil saviours, tree patriots and landscape lovers. It needs people who understand soil, who know how to design and use sensors, data and the internet of things, people who see what’s coming and how to mitigate and reverse negative effects, people who really know how to design and install green infrastructure and future automated robotic maintenance systems. Our landscapes can grow food in amongst all the beauty, with urban food forests. We need new knowledge built on old and we need passion, commitment. A wise government would fund this for the returns will be numerous.

This is the enlightenment, that out of dire stress and trouble, we could really learn how to value, connect with and protect this crazy, beautiful world within which we live. Or we can do nothing and watch it all go to hell. I know which I’ll be doing.

Posted in Adaptive Planting, Biophilia, Climate Change, Design, Ecosystem Services, Edible Planting, Environment, Garden Design, green roof, Green walls, Landscape Futurism, landscapes, living walls, Natural Landscapes, Planting Design, rain gardens, Regenerative Planting, Smart Cities, Sustainability, Trees, Urban Landscapes, Vertical Greening Tagged with: , , , , , , , , , ,

sustainable concrete alternatives
January 30th, 2019 by Mark Laurence
The Roman Pantheon Dome

Concrete is a wonderfully versatile material, which has been in use since Roman times and with it we can build amazing structures that would otherwise be impossible. Unfortunately it also carries a huge environmental cost, caused mostly in the cement binding used. Whilst gravel extraction is also an issue, for that there are some alternatives such as recycled, crushed concrete.

The production of modern cement (OPC – ordinary portland cement) is a hugely polluting process and produces around 8% of the world’s carbon emissions – at least twice that of the aviation industry. Whilst the Romans used a volcanic dust called pozzolona as their binding agent, until the invention of OPC, we used lime, in various forms. Lime too has to be processed by heat and so is not without it’s environmental cost, but it uses less energy to produce than cement and lime concrete/mortar reabsorbs carbon over its lifetime (if exposed to the air), offsetting some of the initial pollution. Moreover, because it is softer, materials can be disassembled easily, for re-use.

cement factory
A typical cement factory

In a landscape, there is ubiquitous use of concrete in a range of structures – walls, paving, sub-bases, ponds etc. some of which could be reduced or avoided altogether. Whilst landscaping will always use an insignificant amount of concrete compared to urban development and infrastructure, there are good reasons to minimise the volume of cement and other hard landscape materials used.

Some of these reasons are for obviously sustainable goals: reducing material/resource input and carbon and other wastes. Equally important in my view, is to increase the soft elements exposed in a garden – soils – and to increase the levels of planting and foliage biomass/diversity. This thinking is about the increase of biophilic benefits.

However, if sustainability is to be given top priority – as it must – then the use of cement has to be reduced as much as possible. This is quite a challenge to us all, as it is not always easy to find an alternative and I don’t suggest for one minute that it should never be used, but it should be reserved for essential structural use only. Even then there may be alternatives. Recycled concrete can make a suitable aggregate (or part of) and low cement alternatives such as CEM 1 reduce the energy and carbon emissions tally.

I have used – and continue to use – concrete in many of my own designs and so this challenge is personal – but then aren’t all sustainability issues.

Let’s look at the different areas of the garden where cement is used:


garden walls
Could these concrete-block walls have been made from rammed chalk?

Walling

Many walls use cement, either in mortar or in concrete blocks as well as in cement renders. In this garden (left) we built retaining walls using hollow concrete block construction on concrete footings with cement render and mineral pigments for the final colouring, with concrete paving slabs as coping. As the site was on a chalk hillside, it may have been possible to construct this using rammed chalk or earth. Indeed, we had a surplus of chalk on the site from the house construction and it would have made perfect eco-sense to have used this to build the walls. The walls could have been rendered using lime based mix, and the coping could have been stone. As the chalk hillside is inherently quite stable, rammed chalk could possibly have been used for the footings too. However, there are so many unknowns, and so few UK examples that it is a risk to do this, especially on such structurally critical terracing. Long-term effects of damp creeping into the walls would have been my main concern.

The cost of rammed earth construction may have been cheaper than conventional construction , both in time to do and in material purchase, especially when the removal off site of subsoil is taken into account.

rammed earth garden walling

Rammed earth garden walling and Cement-substitute coping, GDL.

The picture at right shows rammed earth walls in a sustainable landscape I designed for Grand Designs Live, ExCel, 2006. Rammed earth walls are made by compacting subsoil inside timber or metal formwork. The soil must be kept dry so it needs some kind of footing and capping, here provided by cast copings made with recycled aggregates and partial cement substitute (CEM 2 furnace slag). The gravel to the main paving area is a recycled brick/concrete mix, laid through a geo-grid membrane made from recycled plastic. The aim here is to be as carbon neutral as possible. Planting aspired to be edible (you can eat daylily flowers).

Walling alternatives to concrete include:

  • Cement alternatives/recycled aggregates
  • Rammed Earth
  • Timber walling (railway sleepers etc)
  • Round pole walling (preferably coppiced hardwood)
  • Fences & crib-type embankment walls
  • Brick/stone with lime mortar (brick also has high energy input)
  • Dry Stone walling

reclaimed paving
Reclaimed brick and stone flags have charm and have exhausted their carbon dues. (Apart from cleaning and transport).

Paving

Modern paving is often made from concrete and in some instances it is quite hard to find realistic substitutes. Stone paving is the obvious one but can be expensive. There are many cheaper stone imports available these days, such as Indian Sandstone, which are cost-effective but which carry a high transport and pollution price tag. Reclaimed York paving is highly desirable and of course, reused, so environment friendly but will cost 2-3 times that of cast concrete or Indian Sandstone. Brick is also traditional as paviors but as for walling, still carries a high energy/pollution cost in production, plus is expensive to lay.

For larger areas and drives, self-binding gravels may be one of the better answers, as these form a firm surface, once compacted, without the use of cement. Recycled or local gravels are also acceptable and can be held in place using recycled plastic grids/membranes.

A geo-grid with gravel creates a stable and permeable surface

Paving is one of those areas which highlights the question of just what is sustainable. Is it better to use imported sandstone with its high transport miles but relatively low energy production, or locally made concrete paving with cement and aggregate use, but low transport miles? In either case, the (financial) costs may be similar. There are also ethical and human welfare considerations for stone imported from third world countries, especially in terms of working conditions, health & safety and child labour.

Timber decking can be a viable alternative, especially on sites with changes of levels. Local timbers of the more durable softwoods (like Douglas fir or larch), green oak, Sweet chestnut or recycled tropical hardwoods. All new timbers should be FSC (Forest Stewardship Council) certified. New hardwoods should be avoided even if the have an FSC certificate as there is much illegal timber that still gets sold and even managed plantations may still involves some environmental degradation. They certainly have high transport emissions.

Possible paving alternatives:

  • Recycled stone, brick, cobbles – and concrete slabs
  • Self binding aggregates don’t need cement
  • Fired paviors and tile look beautiful, but are still energy intensive
  • local or recycled aggregates and gravels
  • Decking can be used where appropriate
  • Locally produced concrete slabs minimise transport and can have lower carbon footprint than imported stone
  • Third-world stone may be low energy, but high transport emissions

concrete in a pond

A “natural” pond marginal shelf with protective concrete pad

Ponds

Even natural looking ponds may use concrete in their construction and formal ponds may be dominated by it. Again choice of alternatives is limited.

Concrete is often used to retain rocks and place protective pads over liners, etc. In many places it may be possible to do without concrete pads, which are often used in a “belt-and-braces” approach to protecting a liner. Felt geomembranes are used as standard as a layer underneath and often inside the liner (this may in fact be degraded by contact with concrete) and in many cases, use of additional layers of felt may eliminate the need for concrete. Felt is usually a synthetic, petroleum based product, so also has its environmental considerations (as do liners!). I have successfully used old carpet as replacement for felt, under the pond (I wouldn’t recommend it inside) but be VERY wary of tacks that may have been used. Non-synthetic carpet will degrade over time, which must be born in mind. Of course, before the advent of felt, liners were simply bedded on a layer of sand.

Where rocks and stones create waterfalls, they are used to form spillways and to prevent stones moving when climbed over or stepped upon (an important safety consideration). It may be possible to use hydraulic lime based concretes for this, although I haven’t tried this out. Perhaps well laid rocks, without the use of cement are the key, which would require a careful re-thinking of the construction method. Nature doesn’t use concrete, but then natural streams don’t retain water within an artificial environment (liner). A more holistic approach to water features, where the roof water and household grey water are recycled and the pond design doesn’t hold a fixed level or amount of water, may be the long term answer.


So looking at alternatives to cement raise as many questions as answers and in the 12 or so years since this article was first written, there has been some progress, but not much. Best advice is to minimise the use wherever possible, recognising the long-term durability and benefits of strength that concrete possesses.


First published in 2007, updated 2019

Posted in Climate Change, Environment, landscapes, Sustainability, Urban Landscapes Tagged with: , , , , , , , , ,

Children and water, Boston
January 30th, 2019 by Mark Laurence

The safety of children and water is potentially a controversial issue and I want to make it clear from the start that these are genuine thoughts, with genuine intent but please don’t try and hold me liable for any disasters or accidents that may befall you or your loved ones. I cannot be responsible for your life and any decisions you make on this issue are yours alone. I naturally hope and intend that only good and positive benefit can come from this writing.

Children have an almost universal fascination with water, and parents an equally almost universal fear of it, or of their children being near it. We have all heard the horror stories of children drowning in a pond, or even a shallow puddle and our hearts go out to those unfortunate few who have suffered such a fate.

children enjoying the water

Children enjoying the water

But we seem to live in a fear-driven compensation culture, which stifles creativity or adventure because of the risk of hurt. Authorities and companies cannot afford to take risks, or allow other to take them. Consequentially, more and more things get banned in the interests of public safety. The world may be safer as a result but it is certainly blander.

As a young child I would walk the suburban mile or so to school on my own, ride my bike to visit friends, play down at the dump, swim in the sea and generally have freedoms many children are not now able to experience. But creative play is an essential part of a child’s development and must be catered for somehow. A love and respect of water should be encouraged and this requires contact and familiarity with it. I believe that those most at risk are those who do not appreciate the dangers and those who are too young to.

A burst watermain in Iraq

Out of the disaster of the Iraq war, this burst water main provides a moment of joy for children and adults alike.

It is true, of course, that much of this familiarity, or lack of, will be caused by the geography of your environment. If you don’t have water in daily proximity, it is hard to become familiar with it. If you don’t see with your own eyes how a little stream can become a raging torrent after a downpour, then you will not be aware of the potential danger. Knowing the dangers brings about respect, gives us boundaries beyond which we know that things aren’t safe. In urban areas, the increasing use of WSUDs (water sensitive urban design) in the form of swales and rain gardens is a positive development.

There’s another good reason for us to have regular contact with water and that is a biophilic one. Water is a vital element, which, through modern living, we now tend to regard as no more than a right of utility. But water is the life force of the planet, and so of ourselves. Why else would we want it in our gardens? It soothes us, distracts us from our cares, puts us in touch with those deeper fundamentals of life, if we but let it. Children who experience this often can only be better off for it.

Children playing in a rain garden
Children playing in a rain garden in their family home. When dry, this is empty.

So if I’ve convinced you that it’s good for children to experience water, let’s think about how we might do so with some safety. First of all, young children should be supervised by an adult or responsible elder child, that goes without saying. I don’t advocate that you leave them alone.
I don’t know if there are any statistics available as to the ages of children that have accidents with water, but parental sense will tell us all that children under five have little comprehension of danger and must be watched very carefully, as must those of all ages with special needs. Water features should perhaps be fenced off while children are in their early years.

If there’s not much you can do about water in your wider environment, then you can perhaps create a feature in your own garden.

pond profile showing gentle slopes

This drawing of a stream cross-section could also be for a small pond. Pebbles and shingle make a good base, which the children can play with. Shallow water with gentle slopes mean that if they fall over, they can stand up and climb out.

Steep sides are the most dangerous aspect of a water feature, preventing children (and animals) from being able to stand up or climb out.

Loose paving on the edges of ponds is another risk factor; use only large slabs or stones and make sure that they have only a small percentage of overhang, and are securely cemented in place. Better yet, use a pond-edge design style which doesn’t use paving in this manner at all.

safe play with water

A reminder of what it’s all about – fun! Don’t do this on paving which may become slippery and prevent algal build-up.

With gently sloping sides, layers of subsoil, gravel or shingle will protect the pond liner and give good grip for feet and hands – bare liner tends to be slippery and is more vulnerable to damage. Good construction helps all round, although that is not the subject of this article. If you have an overhanging deck, make sure the water is not too deep at this point and that children can’t get trapped underneath it. Metal or plastic grids can also be built into a pond, sitting just below the water level. These need careful thought as to their siting as they must take the weight of a person without breaking. The danger is these can look very industrial.

As a final thought, if you want moving water but don’t want the depth of a pond, consider a stream garden, where water just flows along a shallow water-course. There is no pond as such and the water just disappears underground into a hidden sump tank, which houses the pump and which is inaccessible..

a stream garden

This stream feature is used by children – the water barely laps their ankles. Stones are moved, small dams made…

In conclusion, there are many things that children learn from playing with water: self confidence, balance, awareness of danger, responsibility, experience of wildlife and of Nature’s rhythms. A careful and reasoned approach is what is required for allow a child safe, creative exploration.

And of course, we adults are all children at heart, too. Play safe.


First published in 2009, updated 2019

Posted in Biophilia, Design, Garden Design, landscapes, Ponds, rain gardens, Water Gardens Tagged with: , , , , , , , ,

January 24th, 2019 by Mark Laurence
The newly installed raingarden flowing during a downpour
The newly installed raingarden flowing during a downpour

Rain gardens are a relatively new approach on how to deal with water in the environment. In the last 10-15 years, there has been a big rise in the use of SUDS (sustainable urban drainage systems), the practice of delaying the entry of rainwater into the drainage system by the use of swales, ditches and ponds. However, this is generally the domain of engineers who are mostly concerned with their pipework; rain gardens, on the other hand, do the same thing, but are equally concerned with aesthetics and ecology – and so are far more exciting. Easily applied to the domestic situation, but the concept works just as well in urban and commercial design. In fact, WSUD – Water Sensative Urban Design – looks set to take on this wider role in the municipal environment, possibly replacing SUDS.

Having built many water gardens in my life, I decided (in 2010) it was time to build a rain garden in my own home, where I could enjoy it and also monitor its performance. These pictures show the just-completed garden, only a few months old; it also rained right on cue and appeared to be working well!

The coil is an old water heater pipe and acts as a fountain - this pond has always been there.
The coil is an old water heater pipe and acts as a fountain – this pond has always been there.

So what is the “philosophy” of a rain garden: why build one? Well, flood prevention is one answer; if you have ever experienced floods in your area, you have directly or indirectly contributed to them. If the rain didn’t fall on your actual roof, it fell on part of the urban fabric that has been built to support you. Another answer is to re-charge ground water supplies; many urban areas have groundwater levels that are dropping due to the fact that rain cannot permeate the land where it falls (95% of urban land is impermeable). Water tables are also dropping because we are abstracting water far more quickly than it is being replenished.

Rain gardens are a great way to re-connect with nature, opening you up to the experience of natural rhythms and process. It will sit there quietly in hot weather, dry, yet still a micro climate for flora and fauna that like a little extra moisture, in the lowest parts, providing free drainage to the drier areas. When it rains, though, the garden comes to life; water from the roof of your house, instead of disappearing down the drain, starts running into the areas of dips and dry ponds you have created, perhaps having topped up your rainwater butts first. Gradually pools start appearing and maybe in a heavy downpour, water starts running between them. How long it then takes to dissipate will depend upon your soil type; I’m on an alluvial soil, so it is very free draining; on heavy clay it might take days for the water to disperse, and this might mostly be from evaporation. This is good too as it helps re-charge the local hydrological cycle, which is also severly lacking sufficient moisture content, and may well be a significant but overlooked driver of climate change. If you have limited space or can’t allow water to rise beyond a certain level (after all, you don’t want to move the flood potential from somewhere further away, to your own home!), then you might need an overflow which puts any surplus water back to drain, or perhaps (and preferably) to another part of the garden. You will have still considerably delayed the timing of water going to drain, as well as the volume.

Here you can see the disconnected downpipe now feeding the chute
Here you can see the disconnected downpipe now feeding the chute

In my garden, I have disconnected one of the main roof downpipes (which it turned out was blocked) and used an old steel channel I found when they demolished the adjacent dairy. We have old cast-iron downpipes so I bought a 90° bend and fitted that to direct the water into the chute. I then dug a channel and partly lined the bottom with plastic, because our ground is very free draining and I wanted to connect this to an existing small water feature, so that this was topped up by rainfall. Surplus water is then dispersed to the sides, through the planting. If I were designing this from scratch, I would put the pond before the raingarden, so this was topped up first. Having said that, this section of the garden has always been incredibly dry and I’m hoping that the ground will, over time, recharge itself and things will grow better. This dryness is evidenced by the fact that we have a young fig growing well, right by the downpipe.

In periods of heavy and prolonged downpours, it may be that the pond will overflow; this will happen at the back and will disperse out away from the house under the bushes. With our soil, I don’t see the need for any further overflow drainage.

The roof section that feeds this downpipe is about 50m2, south facing. We get on average 50cm rain per year, so this should capture 25m3/year. This morning in light/medium rainfall, the chute was delivering 3 litres/minute (nowhere near the rate of a hosepipe). The rain garden is about four metres long and I’m not sure how to measure the drainage rate of soil, apart from having the plasticity index measured in a lab but over time I will use these figures to try and calculate how much water is passing through the system; in theory 25m3/year.


Children playing in a rain garden
Children playing in a rain garden I designed in 2010

I was sent this picture (right) of a rain garden I designed for a client around the same time that I made mine. What a great picture, it gets right to the heart for so many issues about life, play, learning, experience, the elements. We tend to over-design our environments for safety, yet end up sanitizing them to the point where life becomes uneventful and we loose the richness and diversity that being connected to nature gives us. On a rainy day most kids are sat in front of the TV; I think this as a much better option…

The soil in this raingarden is a heavy clay and so holds the water for longer. It is bigger than mine and would need to be to increase the percolation area. You can also see that mine is more planted and this is again a condition of its function – theirs was designed to be a play space for the children (which is why I’m so pleased that it is successful). When they have grown up, it can be planted more intensely. It also created a feature in an otherwise rather awkward, narrow, North-facing space.

Rainwater management isn’t just for large commercial or public-realm sites, it can be done in your own garden too, with multiple benefits to environment, garden, wildlife and of course, you.


First published in 2011

Posted in Climate Change, Garden Design, landscapes, My Garden, rain gardens, Water Gardens Tagged with: , , , , ,