The former home of devoted botanists John and Lilla Leach, Leach Botanical Garden celebrates their contributions to the study of native plants in the Pacific Northwest. A new master plan led by landscape architects Land Morphology includes site and garden improvements for the 16-acre campus, as well as new structures designed by Olson Kundig. The first phase of implementation includes a new arbor, fireside terrace and elevated tree walk, which opened in 2020, as well as an open event lawn, accessible pathway, and improvements to grading, parking and circulation. Future phases will add a series of gardens and a complex of buildings to host a welcome center, offices and gift shop, event center and partner offices.
Leach Botanical Garden’s new arbor and fireside terrace introduces dedicated space for gathering and special events, integrated within the lush landscape of the surrounding gardens. Inspired by lath houses, a type of greenhouse, the arbor features a precise composition of wooden screens attached to a steel and glulam structure instead of traditional solid walls, allowing plants to grow unimpeded up to and around the pavilion. The unconditioned, semi-enclosed space provides protection from the sun and moderates strong wind while inviting a dynamic play of light and shadow. Made of sustainable and durable Kebony, the arbor’s wooden screens will continue to weather as they age, maturing alongside the new gardens. The arbor interior spills onto an exterior stone terrace with integrated gas fireplace, fostering year-round enjoyment.
Designed in close collaboration with Land Morphology and structural engineer Marjorie Lund, an elevated tree walk adjacent to the arbor creates a new experience of the surrounding forest and gardens. Thirty-four feet above the ground at its highest point, the circular walk weaves through mature trees, hovering above the hillside instead of following the topography. Trails and pathways below provide another perspective of the tree walk, arbor and gardens beyond. The metal grate walkway and stainless-steel handrails complement these natural surroundings; the handrails will patina and rust over time, further integrating the tree walk with its context.
“Leach Botanical Garden serves a diverse community by providing a place to gather in nature. The new tree walk provides a unique perspective of the landscape, both immersed in the textures of the forest and looking out over the canopy to the river and hillside beyond. As the starting and ending point for the tree walk, the arbor and fireside terrace establish a sense of embarkation and arrival, as well as a spot to linger out of the elements. The roofline gestures to the tree canopy, while the cantilever creates a dramatic moment – and vital shelter – as it reaches toward the fire.” –Kevin Kudo King, AIA, LEED AP, Design Principal
Lead Consultant, Landscape Architect & Master Planning: Land Morphology
Project Team: Kevin Kudo-King, AIA, LEED AP, Design Principal; Misun Chung Gerrick, Project Architect; Michael Wright, Architectural Staff
Key Consultants: JW Fowler, General Contractor; Janet Turner Engineering, Civil Engineer; Lund Opsahl, Structural Engineer; Reyes Engineering, Electrical Engineer and Lighting Design; GreenWorks, Green Infrastructure; Lancaster Engineering, Traffic Engineer; Winterbrook Planning, Land Use Planning; Friday Group, Specifications; Mitali & Associates, Cost Estimating
Photography: Aaron Leitz