With Spring in full swing and the rains hopefully behind us, those lucky enough to have gardens may be thinking about what to plant and how to do it without creating a lot more work down the line. Landscape architect Thomas Rainer and his team at Phyto Studio in Wash, D.C. consider this in every project they undertake in a practical way, but also as an intellectual concept they call Modular Planting.
“Modular” has been a buzzword and utopian goal in modern architecture for quite some time, and recently “scalable” is common parlance in tech, but how could those possibly apply to planting a landscape?
By calling his idea “Modular Planting”, Rainer posits a planting method that can ostensibly be used in any sized lot and one that leverages biodiversity to ultimately lower maintenance.
We talked to Rainer about this concept, how it has affected his practice and how it will democratize aspects of planting design to enable public agencies, developers, governments, and even individuals to achieve a beautiful self repairing landscape - within their means.
Brick & Wonder: You link the idea of modularity in architecture and industry to how natural systems can function. How do you put that into your practice?
Thomas Rainer: Whether we’re studying natural systems or modern architectural design systems, there are some fundamental organizing patterns that get replicated. In modernism, replication stayed pretty simple and straightforward, but in nature there are a lot of overlapping modular systems which gain visual complexity and biodiversity through scale. We don’t always stand back and look at a meadow or a forest and understand that there are basic patterns in each that give these places their visual legibility.
That said, while trying to promote more biodiverse planting, we still want to have the design strengths that pattern-making and being careful about location and placement can offer.
We love that in a meadow, for example, there is fairly legible pattern making - there’s a base of a handful of grasses into which accents have drifted. These get repeated over and over and gain complexity over time.
In practice, you can simplify that natural phenomenon into modules with all kinds of benefits for designers.
B&W: You’re envisioning a design tool?
TR: It’s a tool yes. Instead of doing a location-based planting plan, you design mixes in different areas (which is much simpler to do) and you figure out components of the mix that will interlock and cover ground. You’re basically designing a spreadsheet more than you’re designing a plan. If you do a good job of understanding how the components fit together in a 1 metre by 1 metre square, you can scale that up.
Once you scale up, you can drift some accents through it and do some some location based upper layer plantings -- screening out a neighbor here, doing some architectural gestures there -- you have this modular carpet as a foundation. It can save time on design, and we really like that!
Often when I go to design a plan, it’s tempting to put a bit of this here and respond to that corner with something different. You end up with more visual diversity than the site can hold. With a modular planting plan, you’re guaranteeing enough repetition of a few base elements to tie that portion of the plan together.
B&W: How do you plan a module?
TR: If you’re trying to come up with a ground cover system, one of the first questions is: ‘Do we have enough light that a meadow-based inspiration makes sense, or is it so shady that a woodland-based inspiration makes more sense?’ It’s a gradient but it’s important to understand the archetypal reference point.
If it’s for a “meadow”, we make sure we have enough cool season grasses and warm season grasses. Those can be exactly the same height and very similar textures, to blend and read minimalistically. Then the rest is just accents on top of that, the seasonal “pop.” This is why the spreadsheet idea is helpful -- for thinking in section instead of plan. What is the narrow plant that can pop through that matrix?
The base module is about a set of really durable things that lock together and provide a long season of interest. And the drifts and patterns that happen above in those upper layers, become a little more more site specific, a little more fun.
B&W: When you want to plant modular, what kind of scale do you need? How small or how big can the site be?
TR: A big pot on someone’s deck can be a module in some ways. Container design is often done the way we’re trying to get people thinking about a landscape planting site.
The whole thing about modularity is that it’s scalable. You can start small, but for massive sites keeping a handful of base modules that creates uniformity across the whole, though there are upper elements that respond to the specific site.
B&W: How do you approach clients with this concept?
TR: Most of our projects are either a new urban plaza or creating a meadow from scratch. When we do green infrastructure, we push for this idea more. Recently, we were having a conversation with a county designer for green infrastructure who’s really pushing back on this because they wanted to do very clean blocks of plants. I could see how much time they were spending on the plan itself. For our approach, we just present one “patch” on a sheet of paper, and a list. Watching her translate this into her pattern and not seeing it was taking a lot of time, but I also think she was pushing for a system that had much less diversity in it.
There are maintenance benefits of a module, say at an airport or a campus. Over time, if there are holes, you can go back and replace it with your base module of 3 to 5 plants. Instead of having to hire the designer to come back and redesign, it’s like a spare tire. It can really save a lot of management headaches!
B&W: You give them the tools.
TR: That’s what we try to do, but there are certain municipal plantings for example where the designer is not sure they’ll be on site until 2 or 3 years later when construction is done. There’s a lot of distrust by the landscape contractor that something this “randomized” is right. The point of randomization in modularity is that you can design mixes where it practically doesn’t matter where the contractor puts anything.
B&W: How much do you see your idea of modular planting in the US and abroad presently?
TR: I don’t see a lot of people using the language. I see a lot of people who are using the stylistic look of naturalism, but that’s not always modular.
It’s really based on new German perennial plantings. They’ve been trialling these truly randomized mixes for 10 or 15 years, getting the mixes really bulletproof. No one’s doing that quite enough here, including us. That’s because you need an academic setting and long term experiments. It’s really successful there because they’re looking into mixes every month of the year, testing for man-hours of weeding, making slight adjustments in the percentages and flower composition to make sure there’s enough color to make these really attractive.
I’ve seen a few of those sites and they’re fabulous. They’re not just throw-on-the-side-of-the-road mixes; they’re jaw dropping in their beauty and waves of color. They are convinced that public agencies can’t hire designers to customize every planting for roundabouts and rooftops. It’s not scalable or efficient.
Architectural modernism, with the promise of democratizing design through modularity has had good and bad effects over time in architecture. There’s aspects of that in planting design. You can design a really beautiful module and know how to site it well.
A big part of our focus is to move landscaping from an aesthetics-based approach towards problem solving. Herbaceous plant systems hold a lot of potential for rooftops and green infrastructure systems and all kinds of needs where there’s some sort of ecosystem service and biodiversity can be functional.
If we use language and strategies aligned with considering a low maintenance goal and the limited resources of public agencies, we have to get away from place-based design.
Featured image: Hermannshof Gardens, photographed by Hans van Horssen
We asked Thomas to design a module for our readers. Here’s the recipe he suggested for a “dry shade patch” a fairly ubiquitous condition in urban courtyards. For the module, choose a size from 3’ x 3’ to 5’ x 5’.
These are all tough plants that will knit together. As for the mix, consider 60% sedge if you want it to appear more finely textured or ⅓ ⅓ ⅓ of each for a more even approach. Get outside!