Living at the edge of ecotones and design

Layered planting in Land Kit

The Design Edge

If ever you’ve ever come across a clearing in the forest, in that place where light and dark converge, you have witnessed the brilliant complexity of edge. Where the edge of the forest meets the edge of an open meadow, populations of flora, fauna, and fungi overlap, creating a more diverse and abundant community than found in either ecosystem alone. This is what makes the forest edge an ideal model in landscape design. 

The great news is you do not need a forest or a meadow to create a sense of edge in your design. And the approach may be applied to both large and small spaces. It is a design inclusive of the multistoried layers of a forest edge from tall trees, to trees that grow in the understory, to shrubs and vines, to the herbaceous plants and groundcover that transition into the open. 

I

magine a design layered beneath the tall, narrow canopy of a wild black cherry, with the broad habit of a flowering dogwood beneath, and below that a dappled willow and a viburnum display brilliant, contrasting hues throughout each season. At the base of the shrubs, coneflower, rudbeckia, snakeroot, milkweed, and wild geranium are carefully interplanted among hellebore, sedges, and low clumping grasses. Climbing skyward is silver lace, prairie rose, or clematis. It’s a colorful display throughout the year and each plant works within the context of the other and may even work in a variety of soils or conditions. 

Where the Sidewalk Ends

Edge in landscape design incorporates additional features: Man-made permeable or impervious surfaces, large or small buildings, and other fixed features like fountains or benches. These, too, serve a similar function found in the natural ecosystem. 

Impervious surfaces, like concrete walkways, allow water to pool and move; they collect grass clippings or leaves and sometimes salt from de-icing. When water runs across these surfaces, it funnels those concentrations of biomass and nutrients into areas adjoining the walkway. This can impact which plants we choose to border those important walkways. Plants with heavier nitrogen demands, those that are salt tolerant, and those that prefer wet feet might be well suited for impervious walkways.

Buildings rising up from the terrain also constitute edge space. A warm, southern-facing wall of a large brick building creates a zone where plants preferring warmer growing conditions will thrive. It can act as a trellis or protect plants from wind; moving the structure from a static element within the design to one that is interactive.

The Computational Design Edge

Big or small, the multistoried edge approach is complicated. Computational design is quickly becoming the standard tool for taking into account the needs of each individual element within the larger design, yielding a thriving installation that will quickly naturalize and remain relatively self-sufficient over time. This means a change to the location of a walkway, building, or slope won’t jeopardize your work. Instead, it may be used to enhance and promote your vision for a space, giving you an edge over the competition.

Images by Chris Landau