Thursday, March 17, 2016

Planting in a post-wild world: Thomas Rainer, Landscape Architect

Earlier this month, the Hamilton Pollinator Paradise team visited the Royal Botanical Gardens to hear a talk by landscape architect and author, Thomas Rainer. “Planting in a post-wild world: Designing plant communities for resilient landscapes” was revolutionary!

Thomas pointed out that by 2030, two thirds of the world’s population will be living in cities. Re-wilding our urban centres will become ever more important from a green infrastructure point of view and also because frankly, “people want to remember a piece of the wild,” Thomas remarked.  “It reminds us of the places that we have lost,” himself, reminiscing about his boyhood in the woods of the deep South—today, all cleared and developed for housing.
 It is good sense then, to plan accordingly and plant and preserve remaining wild spaces.

After having worked with private companies, Thomas arrived at the public sector where the challenge was to figure out how to create active gardens as opposed to “pastoral” ones.

Thomas said the question kept reoccurring: “how do we build urban sites that have high ecological value and are pleasing to people? We need to be thinking about the future, that is, traditional horticulture against ecological planting and can we combine the two; can the two work side by side?”

Thomas suggestion is that if we are going to sell people on native plants, it has got to appeal—the tone in the message of the native plant movement being “too much of a bummer.” His position is that we don’t have to give up on aesthetics in order to do good. “You don’t have to sacrifice your peonies, you can still have native plants. It doesn’t have to hurt,” he said, illustrating that ironically, the best examples of North American native gardens are in Europe! “That’s right! They are geeking out on our Joe pies, which are drop-dead, gorgeous plants!”

The thinking goes, according to Thomas, both movements need to understand that we live in a post-wild world and that (happily) plants’ ability to live in the city is “remarkable.”

Thomas showed us a slide of a green site along a busy street in his own neighbourhood, where despite the salt and the dogs who use it as a public urinal, the plants are thriving, dense and diverse. Meanwhile, the nearby library’s rain garden is supposed to be low maintenance and sustainable, but is not. And why is that? Don’t blame the plants for planting failure; according to Thomas, it all boils down to the difference between how plants grown in our gardens as compared to how they grown in the wild.

Plant communities.

Thomas Rainer: Perennial Garden
This is golden information. In considering garden design, plant communities matter. Thomas explained that the social nature of plants has been almost entirely forgotten by traditional horticulture and we tend to plant individually, whereas in the wild, plants grow together.
“We arrange plants individually, like furniture but in the wild, plants grow in communities as they are social; we are losing the whole society that has developed over years when we plant this way,” Thomas warned.

The way it works is that sites change to eliminate stress. The whole idea of soil preparation is to turn it into pot-soil and yet it is the relation to place that counts. Plants adapt to the stresses of a place, a lack of resources that determines what grows there. “The idea is that stress can be an asset,” Thomas emphasized, and plants communities are adaptive and resilient when they are in social systems.  So how do we work with plants natural interaction, not fight it?
Take mulch. In the wild, plants form green mulch—it’s their job to cover soil, is how Thomas explained it.
Or colour. “In the wild, natural colours can be so harmonious and soul stirring. There are things we can learn from the wild to influence our gardens.”

Designed plant communities

Designed plant communities is the alternative, according to Thomas. He recommends a layered structure to planting plant communities—that is, grow one layer on the other, so that habitat occurs in different niches in space and time living together and there is intensity and diversity in the layers below. Made to grow out of the matrix of other plants, he suggests three layers to a designed plant community: the structural layer (with tall plants like Joe pie and common milkweed); a mid layer that offers seasonal themes (getting colour, with one wave of flowers coming after the next, and shrubs and ferns) and a ground cover layer (this most important layer is a mulch replacement). The diversity of shapes allows the ground to be densely covered.

After more gorgeous illustrations of the intersection of horticulture and ecology, Thomas concluded the talk with the following:
“The reconstruction of nature in our cities will be lead, not by politicians but gardeners and designers.”

Using words like “whimsical” and “playful” to apply to gardens, he suggested that as serious as planting needs to be, we don’t have to take our front yards so seriously!
“Why not meadows on top of gas stations, forests connected across roads, wetlands to clean our storm water?  We don’t need to go away to have a spiritual experience of nature. Diversity creates diversity and resilience—that’s what pollinators care about, if you plant it, they come.”

Check out Thomas's blog here.