Clump or Mingle? by Noel Kingsbury

October 31, 2013

in Articles, General Interest

Now, after all that discussion and noise in response to Thomas Rainer’s piece  about intermingling planting, here is Noel’s reply to Thomas. (and sorry, he hadn’t read all your comments before writing it..)

I must apologise to all those who deplore my  (quote) “relentless puffing of Veddw garden everywhere you can, especially on thinkingardens”  but it appears that Noel has now joined in….

Anne Wareham, editor and Puffer.

High Line, New York, Credit Piet Oudolf Copyright Noel Kingsbury on thinkingardens

High Line, New York, Designer Piet Oudolf

Noel Kingsbury:

Intermingling is inspired by natural plant communities, the free, uninhibited way wild plants grow, densely intermeshing, leaning on each other (or is it supporting each other?), often growing so closely together that separating them requires getting down on hands and knees and literally tearing them apart. Intermingling is an inevitable part of the density with which plants grow, often hundreds per square metre.

Compare this with the typical garden border, where about nine plants share a square metre and barely touch each other. Getting down to really examine how wild plants grow can be a revelation, a fascinating experience in the appreciation of the intense struggle for space that goes on at ground level, and in how complex and multi-layered the micro-habitats are down there. The garden seems almost sterile by comparison.

I think this is a good starting point to think about planting design – this huge difference in density between the natural and the designed. It is one reason why maintaining the conventional designed planting often involves so much work.

I’m grateful to Thomas for his support for myself and Piet and our work, and for so intelligently discussing our ideas. There are a few things he says I would like to pick up on.

“But intermingling plants is not just a design strategy; it is increasingly an ideology.”

Yuk. You mean like Marxism-Leninism or Neo-liberalism? Be careful with words like that! Ideology is exactly what my support for mixed planting strategies is not. In planting design and in landscape design and horticulture more generally, pragmatism is vitally important. We have to start from where the world is and where people are, not from where we would like it and them to be. Intermingling will work in some situations and not others. A lot of that is to do with how it will be managed.

Prairie Morning, an example of the Mixed Planting concept Credit. Schmidt copyright Noel Kingsbury on thinkingardens

Prairie Morning, an example of the Mixed Planting concept

Ideology, schmology

Ecology, unfortunately, has become an ideology, a value system, with political ecology muddying the waters with ecology the science. This has been disastrous for both ecology as a science and for environmentalism. The debate over global warming is the awful example, of a problem that needs technical solutions but which very soon became the focus of a quasi-religious neo-puritan ‘ecology’ movement – very much an ideology and a dogma; the reaction – of big oil funded right-wing global warming scepticism, was therefore inevitable. The resulting inability to have a sensible discussion about this huge issue could be our undoing as a species.

This muddying of the clear blue water between value and science has not been helped either by Dough Tallamy and his rather tendentious book Bringing Nature Home: a good case near to ruined by some bad science and evangelical attitude.

No, intermingling is not an ideology. There will be no 4.00 am knock on the door and no re-education camps for garden designers who block plant Lonicera nitida.

Montpellier Cottage, Herefordshire copyright Noel Kingsbury on thinkingardens

Planting at Montpellier Cottage, Herefordshire, Noel Kingsbury’s garden,

Creating ecologies

In taking my quote from Topos, (= “Creating intermingling plant combinations, whether aesthetically driven or strictly functional, creates an ecology. In a conventional horticultural planting, plants are discouraged from interacting, but when they do, ecology starts to take over. ” Trends in Planting Design. Topos, 83, 2013)  about “creating an ecology” Thomas raises an interesting point, which needs elucidating.

Putting plants together and letting them get on with it, as opposed to intervening every time Monarda ‘Piet’s Perfection’ starts to overrun Chamaenerion ‘Wareham’s Wonder’ (btw. I’d better say I am making these names up – before all the plant-nerds go rushing to the RHS Plant Finder) does just that, it creates a dynamic of interaction, i.e. an ecology. BUT just because we now have the e-word, does not mean that we have something more supportive of the local lesser-spotted mason bee (made that up too). In creating intermingling planting ‘systems’ we are creating artificial ecosystems, but the degree to which these support local wildlife does not necessarily follow.

The extent to which intermingling will support biodiversity will depend on what services the plants can supply: food, roosting, nesting etc. As the Sheffield BUGS project has shown, garden plants can supply a great deal, and they do not need to be local natives (although some specific plant species may help support some particular insects).

Whether intermingled plantings are inherently more supportive of biodiversity remains to be proven – I am not making claims I cannot substantiate. Likewise the extent to which they will prove more stable in the long term remains to be proven. I would however suggest that on both counts they probably will – wildlife thrives on diversity, and complex, multi-layer habitats will inevitably provide more habitat than monocultural blocks.

A key concept here (beware, teacher mode taking over) is the niche, which can be thought of as a micro-habitatand the more different plant species per unit area you have, then the more niches for invertebrates etc. An intermingled planting will also combine plants which occupy a number of niches: upright, sprawly, clump form, etc. The more that space is occupied, the less room there will be for invasive weedy species.

South African area in London Olympic Park designed by James Hitchmough copyright Noel Kingsbury on thinkingardens

South African area in London Olympic Park designed by James Hitchmough

This latter point is part of the wider point that James Hitchmough makes about using seeded mixtures, that plants choose their own places, and establish a series of natural relationships with each other. The result will almost inevitably be more resilient to weed invasion. Designed plantings often suffer from damage (idiot rides motorbike over park planting, visitor-thief pulls plant out and stuffs into handbag etc) – intermingled plantings offer a variety of species to respond to this damage, and so are surely more resilient. We need however to back this up experimentally. Work at the University of Sheffield may contribute to this, but is not yet in the public sphere.

 Monocultures in nature and in the garden

More on that word ‘monoculture’ later. Up until now, commercial landscapes and larger garden planting has relied heavily on single-species (i.e. monocultural) blocks to create visual effects in planting design. Thomas argues that these are quite common in nature. I disagree. Often what appears to be monocultures are not. Anyway, this is kind of irrelevant as we are arguing that monocultures are often dull. We are arguing that intermingling creates far more complex, and visually rich plantings.

Thomas mentions longleaf pine, the classic tree of the American South. From the air it looks like a monoculture, and it used to cover vast areas on an epic scale, but like so much in the US, it was felled with terrifying rapidity. I have an odd feeling that our kitchen table, made of recycled timber, is longleaf. Look underneath (the tree canopy, not my kitchen table) and you often have a fantastically biodiverse ground flora, which is one reason why ecologists get so excited about longleaf.

Look at bracken on a Welsh hillside, or mahonia in an Oregon forest, and you will see nowt but the same plant, but look beneath and you will find other species, even if they are ‘just’ mosses and lichens.

View across grasses, Veddw, copyright Anne Wareham for thinkingardens

(Irrelevant Veddw Puff…..)

I actually think that the occasional block planting creates interest, provides a contrast with intermingling, and, since naturalistic intermingling can sometimes have a bad hair day, helps onlookers to read plantings as intentional. Big blocks of grasses are a personal favourite, so are clipped geometrical foliage shrubs – classic box and yew. Except that we are so unoriginal in our use of the latter. Piet (when he used to use this – he doesn’t much now) or other Dutch modernists like Nico Kloppenburg, create far more interesting effects than those designers who are incapable take this use of clipping beyond classical cliches. Tom Stuart-Smith does also some nice, but rather conservative and ‘safe’ clipped punctuation.

So, for me, there is very definitely a role for the block.

‘Monocultural’ by the way has become a bit of a boo word, largely because of the current fashion in food politics, which is to decry all that is modern and science-led in farming. The word is often uttered between mouthfuls of hand-crafted organic locally-produced sourdough bread along with other denunciations of modern agriculture. I would point out that it is all a matter of scale. Go down to your local organic farm and everything will be in monocultures there too, but just on a smaller scale. So let’s be a little more sensible in our use of the word.

Illustration from 'Planting, a New Perspective' by Noel Kingsbury and Piet Oudolf for thinkingardens

Illustration from ‘Planting, a New Perspective’ by Noel Kingsbury and Piet Oudolf  (My fault it looks a bit lurid. Hard to photograph books)

 Possible pitfalls

Thomas raises some very good points about how bad examples of intermingling could create an image problem for the concept as a whole. Too right. So far, the most highly developed intermingled plantings have been those developed by German and Swiss researchers – the so-called Mixed Planting. See my blog on the subject here:

The Germans are famous at getting the technicalities right and producing things which work. The mixed plantings are designed to be relatively stable for at least ten years. I can well imagine a situation in which nurseries start to put together plant mixes which are not properly evaluated or tested and which look a mess after a few years, or where one component spreads or seeds over everything else. Mixes of plants need to be designed by people with plant knowledge, the designers need to defer to the horticulturalists and ecologists.

Maintenance is a possible weak point. However well designed a mix is, there is the possibility that one member runs riot, the Nepeta ‘Veddw Giant’ swamps and eliminates Lobelia ‘Rainer’s Red’. A mix of interacting individuals sets up a situation where competition between species will occur. Even in a really well designed mix this will happen, particularly on fertile soils where competition for resources often results in a ‘winner takes all’ situation.

Illustration from 'Planting, a New Perspective' by Noel Kingsbury and Piet Oudolf for thinkingardens

Illustration from ‘Planting, a New Perspective’ by Noel Kingsbury and Piet Oudolf

Managing competition requires plant knowledge and experience, and is not appropriate for the mindless exact-specification-type management required by some clients. It is has been a commonplace of naturalistic planting design for many years that this type of planting may require less management than conventional but that this needs to be more skilled. Given how few skilled horticulture professionals there in UK, and USA, this does rather cast doubt on how viable long-term mixed plantings are. Clients need to be committed to making plantings work by resourcing appropriately.

Having said that, a big thrust of the research associated with mixed plantings in Germany has been the work on mowing, and at Sheffield – mowing and burning. James Hitchmough at Sheffield has been working on extensive maintenance techniques in parallel to working on perennial seed mixtures for some time. These may offer us the best option for public space. For private spaces, garden owners can afford to be a lot more experimental.

Intermingling and mixed planting have liberated us from a straightjacket of thinking. But we have a lot to learn. We have only just started.

 Noel Kingsbury

Planting, a New perspective by Noel Kingsbury and Piet Oudolf

(most of the photographs in this piece are from the book)

Noel Kingsbury copyright Charles Hawes

Noel’s Blog





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Katherine Crouch November 13, 2013 at 1:08 pm

Has anyone noticed a gender bias to this dilemma? A review of this year’s clients’ requirements reveals the women revelling in border mingling and their men regarding a mingled border with horror – a mess in their eyes. This gender bias worked out as ten client couples swinging this way, one couple entirely opposite, and two gay client couples both adoring a good mingle within the context of strictly rectiliniar hard landscaping.

One wise wife has given her retired army officer husband lots of lawn to mow in stripes and miles of box hedging to clip to occupy his obsessive desire for order, allowing her to get on with border mingling and grouping in peace. This is a very common division of labour, I have found.

Too small a sample to draw hard and fast conclusions. I think you have to mingle on a decent scale for it to look like you mean it. Small suburban gardens can cope with a dual or triple mingling of ground cover, and some intermingling of perennials of roughly the same height and season, but it is easy to cross the line from mingle to mess in a small garden, whereas shoreline, meadow and woodland mingling looks so right. Wish I had any of the above.

Thomas Rainer November 13, 2013 at 3:32 pm

I have not noticed a gender bias, to be honest. In fact, this conversation was framed by two men with different points of view on this. On a personal level, the people I know who express strong opinions do not fall on gender lines. It seems more based on experience and education to me. Those that garden and design seem to have a higher tolerance for mixed designs than those who don’t.

I definitely perceive a cultural bias, though I’m sure even that stereotype has its limitations. British/German/Dutch tend to have a much higher tolerance for intricacy in planting while American (and perhaps even Japanese) have a stronger preference for visual legibility (neatness).

Interesting point, though.

The Pope November 13, 2013 at 5:06 am

Dear Ben

We are gardeners and we don’t have the time. Natural/Schmatural.

As gardeners We create artificial environments because we are gardeners and not evolutionary biologists who wear a frown.

As you say – there is no nature. There is also no such thing as a stable eco system nor deep ecology. I am a trained ecologist (with lots of acronyms) and your old fashioned notion of stable eco systems was comprehensively torched long ago as quaint and romantic, but complete and utter nonsense. You should enjoy your garden more.

Sorry about that.

Katherine Crouch November 6, 2013 at 8:30 pm

I have just finished a plan for a small courtyard garden (under 50 square metres). One narrow shady border (under 4 square metres) will have a ground cover mingle mixture of one lady fern with purple ajuga, carex evergold, golden creeping jenny, geranium dalmaticum, snowdrops and cyclamen. Even at 1:20 scale, it is difficult to convey the intent pictorially. Looks a mess coloured in by hand. (Could Vectorworks cope with this?)
I reverted to drawing clumps in somewhat interlocking shapes and told the client that they will mingle, backed up with some mingle images off t’internet.
Anybody got any better ideas?

Thomas Rainer November 6, 2013 at 10:10 pm

Look at some of Oudolf’s plans (featured in Noel’s latest book). Some really graphically simple techniques for illustrating a vertically layered design. Very elegant and easy to understand

Stephen November 6, 2013 at 1:04 pm

I’m just a rank amateur … but I wanted to say both Thomas’ original article, Noel’s reply, and the informed commentary below the line on this issue is really first rate and seems to be a total vindication of what Thinking Gardens is supposed to be about. Thanks and thanks again for so much food for thought.

Not that I want to stop or derail the discussion on this topic, but it occurs another aspect of the long term performance/competition/management debate about plantings that parallels this is the shrub/perennial discussion that, under different labels, also touches on “block” versus “intermingling’ approaches. Michael King – who of course comes from as central a place in the New Perennial movement as there is – has been writing some interesting pieces on this recently in his “Perennial Meadows” blog. Often it seems a lot of the best recent writing on perennial plantings on the one hand and shrub planting on the other is a bit like quantum and relativity theory – existing in parallel, but as yet not unified.

Maybe this is another topic Thinking Gardens could pick up, Anne? Apologies if it has already and I’ve been too inattentive to notice, of course….

annewareham November 6, 2013 at 2:49 pm

Thank you, Stephen – a warming comment on cold wet November day.

We haven’t looked at the shrub/perennials issue – though we do have an excellent piece on thinkingardens by Michael King ( Should I ask him if he’d be willing to do another piece or are you volunteering? Xx

Stephen November 6, 2013 at 3:21 pm

Thanks for the kind words, Anne. Well as the lawyers say, volenti non fit injuria – injury does not happen to a volunteer. But this is way above my pay grade I fear, so why not ask Michael?

annewareham November 6, 2013 at 3:42 pm

OK! xx

Susan ITPH November 4, 2013 at 5:05 pm

In a way, being a gardener in an arid climate, I always feel a bit left out of these debates as these are gardening models for damp climates. Completely agree that more research into plant communities needs to be done.

In establishing a new dry land garden, I consulted with a few dry land gardening pioneers about what to put in the dominant plant matrix. At first, it felt a bit like planting by numbers, but once I realized that the plants would reseed themselves and determine their own places in the garden, it became a bit freeing. It would have looked miserable in blocks.

Benjamin Vogt November 4, 2013 at 4:21 pm

Climate change needs technical solutions (the implication being ONLY technical solutions)? For shame, Noel. The very belief that science can save us from our emotions and blatant ris what got us into the whole mess. We need a fundamental ethical shift in the way we live on this planet, how we view and accept other species, and how we care for and love other humans. Our self hate and violence towards each other spills out into the environment – you can see it in tar sands extraction, mountain top removal mining, and over fishing, among countless others. Gardening needs to shift toward respecting and planting for other species in addition to our own aesthetic manipulation / interpretation of nature through garden design.

Sometimes I get quite frustrated with garden conversations because we always have to come back to design and aesthetic – like prairie or forests or marshes think about that, yet we walk among them and are transfixed, dumbfounded, and inspired. Of course, none of these “natural” areas are natural anymore. Nothing is. I don’t know how moved an everyday gardener is going to be by the arguments any of us are making here, but then again, we’re not talking to every day gardeners, are we.

Yes, we need to give up some of ownership in the garden, let plants do what they do a bit more. But I still think we need to advocate for native plants, especially those that serve as hosts for insect larvae. Kind of a big deal. Too often we get stuck on nectar, pollen, nectar, nectar only, which immediately gets equated to visual design only. How limiting.

Yes, we’ve just started this conversation. Thank you. I’d love to hear more of your thoughts on Tallamy. Do you have a post somewhere else?

Katherine Crouch November 3, 2013 at 11:28 am

forbs,,,,will also remember to drop that casually into conversation. Susurrus is also a useful addition to planty one-up-man-ship

Lyn November 3, 2013 at 10:02 am

Wonderful discussion, in the articles and also the comments. Thank you.

Laura November 2, 2013 at 11:14 pm

Having read a number of Noel’s and Piet’s books, and having tried to implement some of the ideas in my garden, two big questions still remain unanswered for me. The pictures of the intermingled gardens are lovely ….but….they all seem to be pretty large and to be very open. So how does this translate to the smaller urban garden which has a lot of shade from nearby trees and shrubs and perhaps, buildings?

annewareham November 2, 2013 at 11:20 pm

Interesting question….

Pecos Paul November 3, 2013 at 4:52 am

Great question, and likely not addressed due to it being out of context with these professional gardens.

As you said, these are lovely gardens, but the scale is too grand for modern homes. For a smaller scale I think a lesser variety of colors intermingling, and zones that transition from sun-loving to shade-loving plants would be fitting.

I believe it was Mr. Rainer who pointed out these intermingled plants still have an obvious pattern. So rather than truly intermingled there are zones of colorfully mixed plants interconnected by swaths of green as best shown in the picture of the Highline—greenspace broken by zones of color.

While the colorful photos from the book are quite beautiful, they’re unnatural in that in the wild we would not see an interplay of so many colors. I believe that’s what Mr. Rainer was suggesting, and I agree.

I feel the Highline is the most naturalistic because of it’s moderation of color. In my experience, and similar to what Mr. Rainer asserts, in nature we often see large swaths of a single color plant as if an island surrounded by a background of a different color (tan, green). As Mr. Kingsbury states, “Even in a really well designed mix this will happen, particularly on fertile soils where competition for resources often results in a ‘winner takes all’ situation.” That’s what happens in nature, a winner takes all situation, that’s why blocks of color does look natural despite what Mr. Kingsbury would have us believe. The other natural scenario is a few different color plants interspersed among one another with a pattern where small bunches form of the same color plant.

Getting back to your question, let’s say you have a continous border with sections of shade and sun, or even spots of empty space exposed to shade or sun. What I see in the wild is varying degrees of green and purplish plants in the shade punctuated with a few brightly colored plants either intermingled or alone in spots exposed to sun as though they were ornamental specimens…not to say that you can’t have many colored plants intermingled in the sunny spots if you wish.

Martin November 3, 2013 at 12:41 pm

I’d like to think there was enough demand for a book on this style of gardening for urban gardens, even a book on the back of a TV series, but I suspect that there is not enough of an audience yet.

The book I find most useful as a starting point for reference is ‘Perennials and their garden habitats’ by Hansen & Stahl (English translation published in 1993) which gives lists of plants according to their garden habitat and growth type. There are other less academic books available listing garden plants according to the conditions they will grow in (i.e. shade, semi-shade) and you could use them and experiment some more! In a small garden it is fairly easy, given a bit of patience, to eradicate anything that is misbehaving and start again with a different plant.

From what you say of your garden the habitats you would be interested in are Woodland and Woodland edge. If you are from the UK then going for a walk in some good examples of ancient woodland (which has better wildflowers usually) is a good idea for wild inspiration and visiting gardens known for their woodland plants/bulbs is another. Woodland gardeners are often keener that their plants self-seed around and mingle anyway, so this style of gardening may be written about without a ‘special’ label.

Tony Spencer November 4, 2013 at 12:44 am

You might also try Noel K’s ‘Natural Gardening in Small Spaces’. For my own part, I’ve managed to create quite a credible naturalistic garden in a smaller cottage context with very mixed conditions – similar to what you describe. (Although I’m in Canada, Zone 5B).

I think it’s a matter of first understanding the fundamental plant palette – the vocabulary of flower shapes and plant structure described in Piet Oudolf and Noel K’s first book – ‘Designing with Plants’ and then choosing a plant list from the more shade-loving part of the spectrum (there’s a fantastic appendix in that same book). It also helps to realize that many of the most desirable shade bloomers prefer some degree of moisture. Dry shade with rootbound soil is the toughest to solve.

Perhaps you’re already aware of all the above through your reading. If you’re more deeply into all this, then you can apply the matrix/intermingling approach described in the latest book but choose according to your conditions. You can create a fantastic matrix out of sedges, ferns, epimediums, woodlanders, ephemerals etc. and layer it out from there…

Ultimately, you can intermingle in a small garden, a single pot, a bouquet. It’s all about opening your imagination to new possibilities and making the most of whatever light crosses your path.

Just don’t forget the forbs!

Jack Sequoia Gardens November 2, 2013 at 6:58 pm

I have thoroughly enjoyed these discussions and commented on Thomas Rainer’s post. Reading all comments on both posts ties the arguments together, and I find in particular both T.R.’s thanks (above)and Martin’s comments very stimulating. And Anne: I too was mystified by ‘forbs’. Must practise using the word nonchalantly whilst talking to visitors to my garden… 😉

annewareham November 2, 2013 at 11:20 pm

Good, Isn’t it? Xx

Katherine Crouch November 2, 2013 at 2:04 pm

Tom, A cooker remaining unchanged for a year? Did you never share a student flat? Entire strata of ecosystems developed on ours, sustainable too.

John Lord November 2, 2013 at 12:24 pm

The purpose of non – food growing gardening is to produce things that are pleasing to the eye. All this talk of monoculture, plant communities (politician’s favourite word), sustainability, etc. etc, is just that, talk. Reading some of the contributions, I can’t help thinking of a socialist workers party meeting (Marxist Leninist, or Trotskyist?) where any issue could be discussed to infinity.
It seems to me that intermingling is just a way to get away from the painting by numbers effect sometimes create by ‘block’ planting. Paradoxical planting schemes using large groups came about with the need to get away from the, one of this and one of that effect ,of the traditional herbaceous border. I’ve only seen an intermingled planting once, it was not without charm but it looked horribly complicated and a nightmare to keep right. It had a bit of the jumble sale stall about it. There appears to be a trend, you could call it the shameless school of garden maintenance, that seems able to turn a blind eye to all types of dishevelment, once there’s a bit of eco about it.
To get away from the dolly mixture look and give a bit of continuity, there appears to be actually underlying block planting using neutral filler type plants. These have been given the name ‘matrix’ plants, which is a nice touch, as any bureaucrat can tell you, use important sounding technical terms and you’re half way there.
I see the Germans are looking at the practicalities of intermingled plantings, so in the fullness of times there will be a ‘system’. Sort of a contradiction in terms.
PS any spelling mistakes on the above are due to the letters intermingling.

Benjamin Vogt November 4, 2013 at 4:25 pm

Maybe we should be gardening with biophilia in our heads more. Since we’re gardening, we clearly are exhibiting some degree of this E.O. Wilson / Erich Fromm term. Why not garden further and deeper? Why just garden on the immediate visual spectrum that serves a human visitor for a short amount of time? Gardens can and should be doing more as we erode the last of nature.

skr November 6, 2013 at 2:19 am

erode the last of nature? you have a very limited view of nature.

Benjamin Vogt November 7, 2013 at 4:16 pm

skr — nature does not exist. It hasn’t for some time. Read up on your Bill McKibben. We need to stop being so near sited in our gardens — the issues are far bigger. Time for gardens to evolve.

Katherine Crouch November 2, 2013 at 9:54 am

Fascinating stuff indeed.
To prepare soil, to plant in groups and mixtures, to evolve the result – in my tiny unfashionable way I’ve been calling that gardening for the last 40 years.

Is it only when it is done professionally and fashionably on a large and public scale that we must call its something else?

Martin November 1, 2013 at 10:45 pm

Another very interesting piece which covers a lot of ground – it is fantastic that we can discuss such a topic with people from all around the world participating.
I’ll put at the start that I love all these new ideas in planting, but one useful way to improve what we do is through constructive criticism; it’s essentially a fundamental cornerstone of science.

Noel, you use the phrase “Putting plants together and letting them get on with it, as opposed to intervening every time Monarda ’Piet’s Perfection’ starts to overrun Chamaenerion ’Wareham’s Wonder’… does just that, it creates a dynamic of interaction, i.e. an ecology” but you later go on to explain that maintenance of such plantings is a possible pitfall; the logic appears to be that leave them to get on with it = ecology, but intervene and it is not ecology. At what level of maintenance intervention does the ‘ecology’ not exist?
There is a dynamic of interaction between the plants in an herbaceous border, but it is a different level of interaction than in one of your intermingling communities. Yes it is a nuanced argument, but it is a more accurate to portray the different forms of planting as points along a spectrum with greater interaction (competition) between a closely planted intermingling community than there is between plants in a traditional herbaceous border, rather than a black and white state where one has ‘ecology’ and one doesn’t.

There is a similar confusion later, in which you state the intermingled planting will “almost inevitably be more resilient to weed invasion” but we find that “Maintenance is a possible weak point. However well designed a mix is, there is the possibility that one member runs riot” which basically is saying that the same problems that occur in a traditional border planting remain with intermingling (i.e. a plant present and growing where we don’t want it to be) – all that has changed is the particular Weedus annoyassimus.

Indeed, you state that the problem of management is so crucial to this new type of planting “Given how few skilled horticulture professionals there in UK, and USA, this does rather cast doubt on how viable long-term mixed plantings are” so that the self-sustaining plant communities being designed may not actually be self-sustaining at all. And yet the UK is justifiably famous for the types of “conventional designed planting [that] often involves so much work” which all these non-skilled horticulture professionals are maintaining. Perhaps an alternative way of looking at this matter is to say that for these new types of ecological style plantings to work long-term, we need to have more training for horticulture professionals on how to manage them – this may have been what you were alluding to with clients needing the resources to make the design work (Although again this does raise the issue that if it is so expensive to maintain compared to conventional garden design, it isn’t really as self-sustaining as claimed).

A quick comment on names:-
I can imagine the term ‘intermingling’ applying to a plant community created from seed where the designer/ecologist chooses the species to use but the respective positions of each individual plant are determined to an extent by chance and the environmental conditions that occur at the time of germination; yes, all packed jostling together like that, then I can see they would be intermingled.
However, Thomas’s suggestion of ‘designed plant communities’ rings more true for plantings created/laid out from plants grown in pots where the designer says “I want that plant to start exactly there in the design and next to this one and so on”. The plants are then left to seed and spread, with the option of being edited at some point by the gardener. The starting point is different, and the resulting community will have to some extent a different appearance.
The term “plant-nerds” is not really used anymore. The more correct term, that the young people are using, is “plant-geek” which is considered cooler, sexier and more ‘with it’ (although to be frank, essentially the same thing).

“Intermingling and mixed planting have liberated us from a straightjacket of thinking.
But we have a lot to learn. We have only just started.” – Yes! Absolutely this! and isn’t it exciting?

Thomas Rainer November 2, 2013 at 3:04 am

Stimulating and incisive. Thoroughly enjoyed your comments.

Tom Mitchell November 1, 2013 at 8:21 pm

What a fascinating discussion! It’s thrilling to read a long series of exchanges about garden design in which concrete is mentioned only once and then derisively.

Noel Kingsbury laments the way that ‘ecology’ has been hijacked by militants from the ‘nature is fluffy’, idiot wing of the green movement. May I echo that lament? Their previous hostage, the formerly unambiguous word ‘organic’, now invokes Duchy of Cornwall oatmeal biscuits, not complex carbon molecules. They are currently attempting to arrogate the term ‘native’, as in ‘native plant movement’.

The big problem with this democratisation of technical terms by – how can I put this politely – technically-challenged folk, is that everyone starts to think they understand what the terms mean. Well-meaning parents start feeding their kids the pulped flesh of expensive ‘organic’ carrots. Gardeners from Wisconsin order ‘native’ seeds from a nursery in Missouri to sow in their Colorado second homes. And designers implement ‘ecological’ planting schemes on cubic metres of imported soil from who-knows-where in the city centre gardens of their environmentally-aware clients.

To come clean, I trained as an ecologist (a proper one), leaving academia after three fascinating years studying one of the most complex of all ecosystems – a tropical rain forest in Borneo. Like all (proper) ecologists I was humbled by the immensity and complexity of the system I was attempting to understand. Of course I failed utterly in that attempt. The thought that I might try to design a stable ecosystem from the ground up would have struck me as risible. It just can’t be done. Yet.

Plants in the real world co-evolve with other members of their ecosystems, remaining finely tuned to the prevailing conditions in which they naturally grow. Introduce suddenly a novel factor (a flood of nitrogen running off from a neighbouring field; a new pest; a plant species with no natural predators) and the ecosystem goes haywire. Duh! No-one is surprised when this happens and yet the same people imagine that they can create ecological nirvana by planting mixed communities of attractive garden plants. They might indeed create ‘ecological’ nirvanas – note the scare quotes – but that is all they will succeed in doing.

None of this is to say that I am against mixed plant communities in gardens. On the contrary, I believe this is by far the most satisfying and aesthetically pleasing way to garden. But let’s be honest. When we intermingle plants from different ecosystems in a single design, we are aiming to please human beings not mother nature. I read and thoroughly enjoyed Noel’s account of his recent trip to Kyrgyzstan in the Hardy Plant Society journal. Like him, I’d like to make available to gardeners and designers some of the extraordinary plants that are out there in nature but not yet accessible. But let us not pretend that, in combining a Ligularia from Kyrgyzstan with an Astilbe from Japan, we are making an ecological planting. We are making an aesthetically pleasing idealisation of the ‘perfect’ ecosystem that we have in mind.

This is, surely, what gardening and designing are all about? Creating perfect idealisations inspired by the flawed models that nature presents us with. Gardens are the most artificial creations of our species. Don’t believe that? Try leaving your garden untended for a year. How much will it resemble the garden you abandoned after a year? Try the same experiment with your cooker, a lamp bulb, your bicycle and you’ll find that they look pretty much as they did a year ago. Without constant, energy-intensive input from their creators, gardens dissolve, almost immediately.

Low maintenance gardens are a contradiction in terms. There’s no such thing and nor should we wish there to be. To garden is precisely to presume, for as long as you live, to do better than nature, in the service of human aesthetics. Why can’t we just get on with making extraordinary gardens (from our human point of view) and acknowledge that this is as hard as any other creative act? What will Veddw be, fifty years after its creator is dead? Unless it has the great misfortune of being preserved in aspic by the National Trust, it will be a brackeny hillside again. That’s ecology!

Thomas Rainer November 2, 2013 at 3:07 am

This is great writing and entirely true:

“Low maintenance gardens are a contradiction in terms. There’s no such thing and nor should we wish there to be. To garden is precisely to presume, for as long as you live, to do better than nature, in the service of human aesthetics.”

And in a way, turns this whole conversation on its head.

Benjamin Vogt November 4, 2013 at 4:31 pm

There is such a thing. I live it every day. Maybe we need to presume less — maybe our hubris echoes too much in all of landscapes. Nothing is really wild anymore, and we now have to manage the entire globe, every little ecosystem. We’ve altered so much, directly or indirectly, that we have now forced ourselves to be landscape managers, gardeners over every life on the planet. I see a problem with this: we don’t have the resources to garden everything. We have a responsibility now to care for plants and animals like we never have before. We can choose to ignore our relationship to them, their worlds we’ve taken over, or we can choose to find a way to re-intergrate ourselves with them; I choose the latter, and I choose it through place-conscious gardening. Here in eastern Nebraska, that’s tallgrass prairie. I guess I’m talking about deep ecology here, if anyone if familiar with it.

andinarcadiaiam November 9, 2013 at 11:08 pm

Mr T. M. has rounded up all the fluff rather nicely and

“Low maintenance gardens are a contradiction in terms. There’s no such thing and nor should we wish there to be. To garden is precisely to presume, for as long as you live, to do better than nature, in the service of human aesthetics.”

pretty well as T.R. says “And in a way, turns this whole conversation on its head.”

I concur.

Though “to do better than nature” is very much a moot point! I am yet to see a ‘garden’ which can do it better than ‘nature’ BUT gardens like James Goldens ‘Federal Twist’ sure gives the ‘Pseudo Ecological’ (Hugh Johnson) a run for its money!

As for “Low maintenance gardens are a contradiction in terms’…yes and no! Lets say one CAN arrive at garden/plant equations with ‘lower’ maintenance levels than many. In my experience often the higher maintenance ensembles are those which use too many inappropriate plant types (lack of local plant knowledge and sufferers of that almost terminal disease plant acquisitiveness…. ) and there are those who must have more garden area than they can cope with……!

As one who has practiced the ‘clump (we have many more evergreens to play with in the Southern Hemi!) und mingle for about 40 years (and did not give the concept a marketable moniker…) I say the more the merrier…BUT please lets not get bogged down with the commodification of all the branding and boxing and talk of movements et al…. as the Scots are want to say…’Get on with IT man’ (woman!)

skr November 6, 2013 at 2:30 am

“why can’t we just get on with making extraordinary gardens and acknowledge that this is as hard as any other creative act?”


anne November 1, 2013 at 5:38 pm

I have thoroughly enjoyed this discussion, thank you Thomas and Noel. Lots of food for thought, and wonderful writing too.
A couple of comments and a question:

I would add to the point about the maintenance factor that also weather and the local fauna have parts to play in the year-to-year changes in such a garden, both of which the gardener has little or no control over, but which may have huge impact on which plants survive, thrive or perish.

As for monocultures, as a commercial farmer (on a very small scale), I can tell you that just as in a forest, my orchard and vineyard are far from a monoculture of plants, despite the fact that it was planted that way. Nature has a way of filling a vacuum , and we don’t fight Her too hard. I don’t think my farm is an exception to this.

Left out of this discussion are Japanese gardens, which are very formal gardens often meant to emphasize some aspect of nature….any comment, or would this be another thread entirely?

Finally, Noel, I will look for your book the next time I gather the wagons for a trip into town, but meanwhile I’m dying to know what those fabulously colorful gardens in your photos look like when they’re not blooming?

Tristan Gregory November 1, 2013 at 6:52 pm

It probably is another thread but as we seem to be mellowing towards cultural context these Japanese gardens are the product of a Neo-Confucian influenced society; the gardens are intricate correct and should be understood – viewers responsibility.

We on the other hand are noisier and prone to changing our minds so while there is much to admire about the beauty and order of such gardens they are not reflective of the society we belong to; we’re not up to their standard tending rather to the obvious and vulgar.

bernhard feistel November 1, 2013 at 1:29 pm

Since “ideologies” are embellishing this debate, the gardener Alexander Pope springs to mind:

“For Forms of Government let fools (no offence meant, B.F.) contest; whatever is best administered is best”. By which I mean the personalized, flexible and open-minded interpretation of a theme or theory.

Or in other words, I am somewhat with Tristan here.

And just another thought:I feel a little uneasy about the German model example, despite Karl Foerster, Weihenstefan, Hermannshof… Perhaps there is a different approach to public spaces there, but with regard to exceptional private gardens (however controversial), Britain is still far more inspiring and varied to me. I can’t think of a German Little Sparta, East Ruston, Garden House, Veddw… (Yet)

Katherine Crouch November 1, 2013 at 12:29 pm

most interesting pieces.
The devil is in the development and maintenance. Other plants will
insist in joining a monoculture. Blocks spread like wildfire or die out
in patches. Mixed planting become dominated by thugs.

Against my advice (rich clay soil, non-gardener garden owner) my client
made a wild flower meadow. It is indeed full of wild flowers. Nettles,
thistles, docks, burdock and brambles. Sigh.


Marie McLeish, My Garden Coach October 31, 2013 at 10:27 pm

Both Mingle & Clump by Thomas Rainer and Clump & Mingle by Noel Kingsbury are cracking good reads. Thank you both. Its the stuff of passion mingled with opinion, knowledge and planting know how. Not to mention the entertaining experiential informed commentary.

Whether you clump or mingle- the pivotal point influencing the success of the planting scheme will be the level of detailed plant knowledge, and the ground condition and aspect. My favorite gardens are those where the planting merges carpet like. Schemes where the spaces of bare earth in between are kept weed free just hum of ‘maintenance is all that matters’ and frankly do not inspire! Still reading Planting, a New Perspective (Inspiring) and a long time fan of Planting Design, Gardens in Time and Space, both by Piet Oudolf & Noel Kingsbury they bring together critical research, the aesthetics of planting design and the disciplines of plant ecology and performance. While the approach work brilliantly in larger sites,and public spaces the average gardener might find it daunting on a small scale. Regardless I would advocate having a go in more intimate spaces. It’s a crying shame that so many urban front gardens are a melee of concrete, pebbles and may be if you are lucky, a tub with a desiccated shrub! An opportunity exists for communities along these streets to have a go with mingling or clumping plants matrix fashion, renewing seasonality in structure and form, and encouraging nature to thrive. Beautiful to look at and enjoy too.

These matrix planting plans get to hold you in their power. You know they need to be experienced as well as looked at, all the while raising your consciousness with regard to form, structure, texture and color at one level, and as your eye is drawn in you spot a bird feeding, a butterfly drinking nectar, a hover fly, a bumble bee and hopefully a honey bee.

The second pivotal point influencing success is sufficient knowledge of how nature will populate and use the habitat that develops as the planting matures: nectar flow, seed supply, berries,scaffold plants for perches, thickets for hiding, cover and nesting. The plant communities develop their own hierarchy toughing it out for their survival. The more genteel specimens in the mix may have to be sacrificed in favor of less intensive management.

Both articles mention maintenance as a potential pitfall. True, the habit of weeds needs to be understood at least as well as the key plants. In her book Gardening in Tune with Nature (2005) Pam Lewis describes the process of ‘Managing weeds’. Many are tolerated for much of their life cycle particularly if they add interest at transition points in the garden. Then just before seed is set, the weed is culled ruthlessly, robbing the seed its opportunity to ‘pop, ping,spiral earthwards or just drop locally’ Eradication is not the objective here, rather a ‘some and some’ approach where some are pulled and the weed population weakened, and some left.

Roll on the Clumping and Mingling planting revolution….its exciting! No plot too big or too small.

Gaynor Witchard October 31, 2013 at 7:57 pm

Wow! Great writing – and I for one use clumps & intermingling when planting, simply because the spaces I design are small and need to work harder. Clumps of spring bulbs underplanted with early annuals/biennials in drifts is one such method I use…however the annuals/biennials naturalise and spread themselves in drifts without much help from me! Perennial plantings of Geranium, Leucanthemum, Anemone japonica, Verbena bonariensis and yellow loostrife (not everyone favourite but it holds a steep bank in place!) is one such mix in my own garden.

Tristan Gregory October 31, 2013 at 7:28 pm

While clearly a great deal to commend the many ideas and techniques that contribute to this intellectual approach to planting I just don’t feel it. To be truthful it seems more like a discussion of seed mixes for the perfect lawn than a path towards the creation of meaningful, resonant spaces.
As a means of improving public spaces then I am probably a convert, if the appropriate research is being undertaken regarding maintenance and resource efficiency then I’d be delighted to see the demise of the green waste but for me that is as far as it goes.
When it comes to gardening I am no sort of “ist” merely an artisan and I just can’t reconcile the approaches.

Thomas Rainer November 1, 2013 at 1:17 pm


A great response, thoughtful and clear. I very much appreciate the elucidation. The great things about forums like the one Anne has hosted here is that it lets the ideas breathe and grow in a way that books and journals can’t always do. So thank you. We’ve all benefited from your willingness to roll up your sleeves and jump in this conversation. Which is really one you started . . .

Nuance is everything. This smaller discussion about how plants get arranged is really part of a larger one about how planting design should respond to the environmental challenges of our time, right? You’ve spent much of your career wrestling with these questions (to all our benefit). And we are light years closer to having answers than we were two decades ago. But as you say, we still have much to learn. The answers-if there are answers-will not be simple declarative statements. They will be nuanced. The solutions will be all about the details: the technique, the implementation, the management.

So I agree with what you’ve written. You make many great points, and clarify others which helps me understand better. The differences we may have are more differences of tone and style than substance.

As I’ve been reading the comments and thinking more about this, it occurs to me that part of what underlies my reaction to “intermingling” as a solution is partly my own cultural baggage. Europeans–particularly British, German, and Dutch traditions–have a much higher tolerance for complexity in their plantings. We Americans have never had anything like a cottage garden tradition. Or much of a garden tradition, period. Like you, I am entirely convinced that naturalistic planting design can provide a powerful alternative to traditional landscaping. Especially an alternative aesthetic vision.

But I am surrounded by skeptics. One the one hand, the American public has very little tolerance for wildness in their landscapes. And on the other hand, the professional landscape architecture community is for the most part still smitten with modernism (or some kind of formalism). Add to that a very low level of horticultural knowledge and skill, and you have one tough sell for mixed planting.

But that resistance is softening. So for me, I am rather feverish to find a landscape aesthetic that serves as a gateway to a more natural aesthetic. Like you, I am rather fascinated with the German mixed planting approaches. They really are working out the techniques for us, but the aesthetic they create would be met with much resistance here. It tends to create a very intricate planting.

And at the same time, I am thinking more about wild plant communities. The more time I spend thinking and visiting them, my reaction is the same: despite the intermingled diversity present, they are incredibly calm, heavily patterned plantings. There are only a handful of visually dominant species. Very different in look from the intricate look of a designed plant community like Hermannshof. Of course, a place like Hermannshof is meant to be more stylized. The heavier representation of forbs in these plantings is intentional: a way to make it more gardenesque. But to me, Hermannshof feels very disconnected from the habitats it is supposed to represent precisely because they do not represent the visually dominant plants in roughly the same proportion as the wild community.

So at least for me, the emphasis on intermingling as the new direction for planting design is good, but what would be more useful is to focus on strategies for mixing that still preserves a high degree of visual legibility. Let the landscape architects still use impossibly large masses (they will anyways); but convince them to embed those masses with several layers of compatible forbs that add diversity and life. Help the masses understand the importance of ground-covering herbaceous plants (the less than sexy Carex, grasses, ferns, and other matrix forming plants) as the largest percentage of the mix, as opposed to charismatic forbs (Echinaceas) that flop without their matrix partners.

For me the central issue is the development of a new aesthetic that is genuinely more durable, enduring, and beautiful. An aesthetic that persuades not just the rather small subset of ecologically minded gardeners and designers, but the masses. For me, that “look” must include calm, visually legible plantings as well as highly mixed ones. That doesn’t mean monocultures; but perhaps more matrix-style plantings.

What is at stake-as you point out-is quite a lot of land that makes up our managed landscapes.

Thanks again for participating in this dialogue, and for all the great work you do in elevating the conversation.

annewareham November 1, 2013 at 5:41 pm

‘forbs’ ? Thomas?

Tony Spencer November 2, 2013 at 3:45 am

Since you ask: A forb is an herbaceous annual, perennial or biennial that is not a grass.

Much thanks for a tremendous read and intermingling of minds.

annewareham November 2, 2013 at 9:35 am

Thank you. Xx

Martin November 2, 2013 at 8:46 am

Definitely agree with you there – “For me the central issue is the development of a new aesthetic that is genuinely more durable, enduring, and beautiful” and for public plantings there should always be consideration of what the audience can cope with.
Also, the more we get different interpretations of this new way of using plants the more interesting the gardens become, so we don’t just swap one way of doing things borders (with physical work) for another – intermingling (less physical work but more mental work) just because it’s the in thing to do.

Benjamin Vogt November 4, 2013 at 4:35 pm

Maybe to get to that new aesthetic, Thomas, means we have to be even more patient with garden establishment? Maybe it doesn’t just take 10 years for the garden to mature to a good first level, but 20 or 30? Does a more natural look, that seems to ask plants to sort things out for themselves and mingle at the cocktail party, mean we have to wait longer for them to find their niches? And YES to sedges!

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