Sunday, August 19, 2018

Ecological Planting - The revolution will never be bought at the garden centre.

A Larry Weaner garden in New England. To be featured in the October issue of Gardens Illustrated. Photo credit: Claire Takacs

Who remembers that wonderful Gil Scott-Heron rap song “The Revolution Will Not BeTelevised”
The revolution will not give your mouth sex appeal
The revolution will not get rid of the nubs
The revolution will not make you look five pounds
Thinner, because The revolution will not be televised.

I feel like coming up with something similar for 'ecological planting'.

There is much talk of ecological planting? Is anyone actually doing any? Or is it all talk?

What is ecological planting anyway?

And does it matter?

Well, it is always nice when words convey meaning we can all agree on, and in this case we are not just talking about something with the equivalence of an artistic movement but also something that a direct impact on biodiversity. There is always the ever-present danger of 'greenwash', something sounding green and good for the environment but in fact just a trendy feel-good facade.

Years ago (late 1990s) Nigel Dunnett and James Hitchmough had made the distinction between 'naturalistic' planting and ecological functioning, i.e. you can have 1) something that looks natural but is either completely static or dependent on quite intense management or 2) a planting that is to some extent dynamic, i.e. its components are going through active processes of seeding, spreading, dying. An ecologically functioning planting should have some level of stability, so it can continue to exist without too much human intervention. One example might be a meadow, which is dependent for its long-term survival on annual mowing but otherwise is relatively stable from year to year.

Now, it should be pretty obvious that there is a lot of good planting design that falls into the former category, natural looking to most observers but in fact not in the remotest sense a dynamic self-sustaining plant community. Anyone with any knowledge of basic plant ecology would not be fooled, and more importantly neither would most invertebrates seeking a habitat.

Compare such a planting to a natural or semi-natural habitat like a meadow and it is immediately obvious that any horticultural planting is almost absurdly low density. In a wild habitat, gaps between plants are often difficult to see, whereas in a human-created planting they are usually pretty obvious. It is possible to get tens of species in one square metre in the wild, whereas most artificial plantings have 4 or 5 plants (never mind species) to the square metre, or 9 at the most (this figure is significant, as we shall see).
Six species in shot, but could do better, BUT much greater species density than most gardeners aim at: close-up of one of my old trial plots in Herefordshire

Think about this disparity in density in habitat terms – the artificial planting will be almost inevitably far poorer. So, before doing too much slapping ourselves on the back about what a good turn we are doing for nature, let's just consider the absurdity of thinking that just because we've got something that looks rather natural, and/or is composed of locally-native species we've created something that is any way equivalent to a natural habitat. If it's got gaps between plants its ecological functioning will be below par, and it will be unstable (space for weeds). Ecological planting it is not.

To go back to Gil Scott-Heron:
The revolution is not because you got the right plants for the habitat conditions,
The revolution hasn't happened because you've gone all native
The revolution isn't ticking all the species on the list of bee-friendly plants from Home Depot
The revolution is not just about looking all wild and woolly,
The revolution will never be bought at the garden centre.

Above all, because the whole 'perennial revolution' has happened alongside the interest in naturalistic planting there tends to develop the thought in too many heads that “it's all perennials therefore it must be ecological”.


At the same time however, let's remember the much-quoted Owen research  which showed just how many insect species an average (i.e. not in the remotest sense ecological) British garden contains. This shows us the exciting possibilities! Imagine how much biodiversity a garden could contain if it had something approaching the density of real habitat AND the range of diversity that most gardens include anyway (trees and shrubs and perennials and climbers).

How do we measure garden biodiversity? Not easy. Never is. Owen simply counted species not their frequency of occurrence in comparison to 'nature', and if you look through the academic literature it rapidly becomes apparent that there is no easy, or for that matter difficult, way to measure overall health of ecological functioning. What sometimes is done by researchers is to take one particular aspect, usually a category of insect, and use that as an indicator. Trouble is, it will be different for different types of habitat. Currently there is much focus on pollinators. And much trendy nonsense spoken; trouble is - where there are marketing opportunities, pseudoscientific gibberish soon follows. Pollinators could a relatively easy group to use as an indicator for ecosystem health. The trouble is though that I could imagine a garden planted with pollinator-friendly plants buzzing with bees etc, but which actually supported very little else such as ground-level invertebrate biodiversity.

How much do we want to create gardens that are genuine biodiversity reserves? If we really want to create plantings with an ecological functionality that approaches equivalent natural environments, then we must be honest in making clear the distinctions between these and plantings that merely look a bit wild.

Anyone who sows a meadow or prairie and got it to a point of reasonable stability will have created a functioning ecosystem. BUT,  this won't be a garden but only a habitat restoration. In the US however, practitioners such as Larry Weaner have started to tweak seed mixes to create what are essentially ornamental versions of natural ecosystems. The much richer flora of North America (compared to much of Europe) allows this. But it still is not what most people would regard as a garden. BTW there's a great example of his work coming up in Gardens Illustrated soon.

So, any other, more garden-like, examples?

The best can be seen in lightly shaded habitats where light levels knock back grass growth, the main enemy of plant diversity (dense north European grassland could possibly be worse in ecosystem functioning than your average garden). Or indeed other, slightly stressed habitats. Established gardens sometimes have amazingly dense and varied combinations of woodland species in such places. One of my favourite such areas is the woodland garden at Wisley (the one near the new glasshouse): a whole range of rather competitive woodland edge species, native and introduced fight for supremacy, and with the possible exception of one patch of comfrey, nobody seems to be winning. Maintenance seems to be limited to the odd clear-out and re-plant, which I suspect has the effect of 're-setting the clock'.
A spectacular example I saw recently was as Innisfree in NY State, where a shaded rocky slope is home to a bewildering variety of naturalised garden plants, mostly non-native species, but mixed with natives. According to Kate Kerin, the Landscape Curator there, this would have been planted up between the 1930s and the early 2000s and gets only limited maintenance – mostly pulling of grass and tree seedlings. One of the sights in this fascinating, but also rather precipitous, place is a big patch of Coreopsis verticillata and Convallaria majalis growing completely intertwined, two species of very different habitats (sun, dry and shade) no gardener would have put together.

Nigel Dunnett's planting at the Barbican in London may be only a few years old but shows enough self-seeding to suggest to me that it could stabilise as a genuinely ecologically functioning planting. It's essentially a green roof planting, so seasonal drought will limit grass and weed growth.
James Hitchmough's various plantings, all created from seed, should theoretically, lead to semi-stable ecosystems, but I have personally not seen one that convinces me, yet, although some of the Queen Elizabeth Olympic Park ones may yet do so, and I have heard good reports of others.
The Barbican, a Nigel Dunnett planting, effectively a green roof, lots of regeneration

In two gardens in Herefordshire, I feel I have got pretty close to achieving small areas of genuine ecological planting, with really dense species intermingling. In my last garden I ran a trial for seven years which went someway to convincing me that, in the most challenging situation of all: fertile moist soil, full sun, this might be possible. These conditions favour the growth of strongly competitive plants which could possibly swamp everything else and most dangerously, favour weedy grass growth. This never happened (success!), but somewhat disappointingly, an analysis of every 10cms square after seven years, revealed that there were still a lot of gaps. In reality these could probably be filled with ground-level creeping species and more seeding short-lived species. More species need to be packed in to really create a dense multi-layer habitat. I, like everyone, have a lot to learn here.

What about Oudolf-style perennials or German Mixed Planting systems, which use long-lived perennials at around 8-9 plants per square metre? They are designed to be relatively stable, but also allowing for a certain amount of self-seeding. They seem like a very good starting point for a genuinely ecological planting. Not TOO stable though, as that can preclude any ecological functioning (think prostrate cotoneaster ground cover).

And, on the subject of Piet Oudolf, he has created one of the most interesting and successful combinations of an ecological planting (native grasses and wildflowers) and non-native perennials. See here:  This approach is certainly one which deserves much more research: but very dependent on having low fertility soils.
Piet Oudolf perennial meadow at Hummelo, not typical of his work but possibly one of the most interesting things he's ever done; combining genuine ecological functioning and good looks

The fact is that we have hardly begun to explore the possibilities of what ecologists are now calling Novel Ecosystems: “a system of abiotic, biotic, and social components (and their interactions) that, by virtue of human influence, differs from those that prevailed historically, having a tendency to self-organize and manifest novel qualities without intensive human management.” quoted here.
From now on I'm going to talk about: NOEs: Novel Ornamental Ecosystems.

Where do we go from here?

How do we assemble plantings that look good, with species from multiple origins that are so dense that they can offer wildlife as many opportunities as natural/semi-natural plantings, and which are stable enough to make maintenance easy?

This is now the challenge. Let's raise the bar.
Wrong time of year for the flowers but a shaded bank at Innisfree which includes a bewildering range of Novel Ornamental Ecosystem biodiversity

Thursday, August 2, 2018

We have the new perennials but where is the new perennial garden?

A recent blog post by Marc 'le jardinier' is tries to provoke a discussion about whether the so-called 'New Perennial' movement has had much of an impact on British gardens. His conclusion is 'not much'. The implication is that this should be a surprise. In many ways I agree with him but I don't think it is a surprise. So, here I'd like to do one of those roundups where I look around and survey the scene and ask, “what has really changed?”. Apart from the interest in this as gardeners and landscape designers, it's an opportunity to think more widely about why we garden and about the way that cultural change happens.

The 'New Perennial' moniker is an annoying one anyway. Anything with 'new' in the title inevitably comes with a date stamp in the near future. It actually dates to 1996, when Frances Lincoln decided, in one of those moments of genius that made everyone else in publishing think “why didn't I think of that?”, to use it as a title for a book project I had with her company.

A Nadia Malarky designed garden in Columbus Ohio
What the 'new' and the 'perennial' flag up though is that there have been enormous changes in British, and American gardening over the last thirty years, and one of the biggest has been the revival of interest in herbaceous perennials. Looking back to the 1980s, it is actually hard to imagine how people gardened with so few perennials. Anyone who is too young to remember this time would be astonished now at how garden centres and nurseries almost entirely sold shrubs and bedding, with perennials a distinct minority interest. On a recent trip to the US (primarily Ohio) I was amazed by how many gardens featured perennials, mostly echinaceas and rudbeckias of course. In the past there would have been lawn and a square metre of pink phlox if you were lucky. A great sense of satisfaction, and pride, at having been part of the movement that has enabled this.

What people have done with the perennials is another thing. As with the grasses, which have been an even bigger shift since the 1980s (back then NOBODY in Britain grew grasses apart from eccentric prophets in the wilderness like Roger Grounds). On the whole they have slotted their geraniums, monardas and Carex testacea into the garden format they had before. Which generally means the borders around the lawn; the ingredients have changed but the recipe hasn't.

For those of us, like the people reading this blog post, who are (and trying not to sound too superior here) part of the gardening 'elite', acting as opinion-formers etc., the mismatch between what we think people should do with 'our' plants and what they actually do with them, may be considerable. But take an analogy – think of the amateur art shows we have all been too, usually held in village halls. How many of the artists have done what the art elite seem to describe as art: smear mud on the walls, pile up bricks, carry in their unmade bed and leave it in the middle of the room? None. Elite thinking about art has not penetrated very far into popular culture (do I hear sounds of relief?). No-one in the real world seems to want to practice 'conceptual art'. 'Art' for most people does mean: painting, beauty, colour, form, memory, landscape, portraiture, while Tracy Emin's unmade bed at the Tate is little more than a provocation to chattering class dinner parties.

Am I making an analogy between conceptual art and 'new perennial' gardening? Only in as much as they are both elite concerns which have not penetrated popular culture. Personally, I think most conceptual art is crap and new perennial planting isn't. But then I'm not a conceptual artist whose just had a fat grant for hanging tampons on a washing line or whatever.

Most people garden to relax, unwind and feel close to the sanitised version of nature that the garden presents us with. They are not interested in trends, concepts and 'movements'. They want something that looks nice and makes them feel good. This means that gardening is one of the more conservative of the arts. And who are we to criticise what people do in their spare time? And another thing – naturalistic planting is systems or community thinking. Its about creating plant mixes and most gardeners do not think like that. They think only in terms of individual plants and how they like them, and maybe find good neighbours for them. They are driven by what looks nice down at the garden centre or the nursery. Fair enough. I don't think we could expect otherwise.

And another thing! Much of the naturalistic planting featured in garden magazines is large-scale. It's Piet O doing parks or those designers who specialise in large country gardens; some medium-scale and more 'average' gardeners certainly get featured, but there are surprisingly few who really carry it off. One who has tried is featured in the September issue of Country Living; Jo Ward-Ellison in Gloucestershire. Size puts people off. Unnecessarily I think. On of the virtues of naturalistic planting is that it is about building plant communities, which are scaleable and work over a range of sizes. Take a Piet O planting and in many cases you could chop a bit off and stick in your suburban garden to replace the oh-so-boring lawn and with a bit of fiddling it would still look good. The main difference would be that you would be forced to be closer to a lot of the plants so you would appreciate them in a different way to the 'big picture' view. Perhaps no bad thing.

More pointedly, I'd like to ask about how much designers and the landscape profession have taken on board 'new perennials' or as I'm going to call it from now on, naturalistic planting? There is no doubt that the range of plants has been massively increased, although there is still a problem about how you sell late-season perennials, as they generally look so awful in pots. The garden centre industry has never really tried although internet sales have come to the rescue to some extent. The huge growth in the garden design profession has gone hand in hand with the perennial explosion although for the most part perennials are used within those designs in a relatively conventional way.
Most garden designers still seem to be at the level of slotting individuals together than creating functioning plant communities.

The landscape profession, largely under pressure from clients anxious about the maintenance costs of what they pay for, have been cautious, understandably. For the most part, they also lack the plant knowledge to know how to use perennials. Many are anxious to learn, as I can see from the folk turning up at my workshops ( and Knowledge about the long-term performance of perennials is also poor; something I am endlessly banging on about, and which I try to address in the workshops.

The big change in British gardening, and one also increasingly being followed elsewhere is the 'wildlife gardening' movement. Supported by a strong grassroots interest in conservation and at what we might call the 'official level', i.e by the RHS, this has made a huge impact, and again it is difficult to imagine how this could have happened without the perennial revolution. It stresses diversity, that varied habitats are the best thing we can do for nature, something that the good old British 'mixed border' addresses rather well. Crucially, the wildlife gardening movement also does something else – it gives gardeners permission to be a bit untidy: weeds, dead leaves, unpruned shrubs. That has probably helped a great deal.

So, changes there have certainly been, for the better, but we still have a long way to go. Changes in garden practice can take a lot longer to take place than in many other spheres of human activity. More crucial than the largely aesthetic concerns of New Perennial gardeners are the impacts that gardening and landscape practice have on sustainability and wildlife. I'll be considering that next and ask the question “is anybody out there actually doing ecological planting?”