Richard Lyon, RLA ASLA

Partner, Principal Landscape Architect

A native of New Zealand, Richard is well known throughout Wilmington, DE and Southeastern Pennsylvania where he has designed and managed installation of many fine home landscapes.

Extensive travel and living abroad allows him to bring a unique perspective and creative approach to long-term landscape solutions.

His strength lies in his intense creativity, innovative problem solving and passion for his work. Richard has received recognition with both national and regional design awards.

He specializes in large-scale residential projects, the revitalization of older home landscapes, and designing for new homes.

Richard earned a Bachelors Degree in Horticultural Science from Massey University, New Zealand and studied as an international horticulturalist at Longwood Gardens.

He also won awards at the Royal Horticultural Show in Chelsea, England.

Accreditations & Memberships:

• Registered Landscape Architect in Pennsylvania and Delaware
• Chairperson of the Kennett Area Parks Authority
• Natural Lands Manager at UUSMC Delaware

Laura R. Miller, RLA

Partner, Principal Landscape Architect

Laura has more than 25 years of experience beginning with skills acquired from previous Architectural, Land Planning, Environmental and Design-Build firms since 1983.

Laura joined Wallace in 1990 and became managing partner in 1998. Her project experience includes numerous variations of custom home garden design throughout the Delaware valley. She works closely with clients to interpret their needs and desires, and balances them with budget constraints.

Laura is inspired by the creation of new environments. She enjoys the opportunity to work with all styles of homes incorporating each individual’s lifestyle and taste, then blending it seamlessly with the surrounding environment. Laura includes natural elements into the designed landscape by incorporating water, stone and a variety of plant palettes. She also finds ways to integrate green practices, including recycling onsite materials and creative ways to manage storm water. A recipient of many awards for her creativity, Laura designs landscapes of enduring character and dedicates experience and vision to every project.

Laura earned a Bachelors of Science in Environmental Planning and Design from Rutgers University, Cook College.

Accreditations & Memberships:

• Registered Landscape Architect in Pennsylvania and Delaware
• Member of American Society of Landscape Architects
• Member of Women Entrepreneurs Professional Services (WEPS)

Awards:

• Gold Award – Pennsylvania Landscape & Nurseryman’s Association (PLNA)
• Excellence in Landscape Design “Residential Hardscape”
• Bronze Award – PLNA Excellence in Landscape Design
• Merit Award – Environmental Improvement (PLANET)
• Honorable Mention – PLNA Excellence in Landscape Design “Historic Restoration Garden

Eric T. Leeson, RLA ASLA

Principal Landscape Architect

Eric joined Wallace Landscape Associates in June 2011 after a 16-year tenure with Terrain (formerly J.F. Styer Nurseries), nine years with the Philadelphia based land planning firm, John Rahenkamp Consultants, Inc., and a career start with Land Design Research, Inc., in Columbia, MD.

A lifelong Delaware Valley resident, he earned a BS w/ distinction in Landscape Architecture from the Pennsylvania State University in 1986.

Eric’s expertise and interests focus primarily on landscape design, construction management/team building and coordination of design implementations for residential clientele. In addition, Eric has extensive experience in residential, commercial and institutional land/site planning and development.

Application of a hands on field design and management style achieves an optimum result, responding to both the client’s vision and the property’s capacities and potential. Eric has a special interest in The Sustainable Landscape Initiative (SITES) specifically, as it applies to the residential landscape and coupled with the understanding of our regional considerations. The preservation and adaptive reuse or restoration of existing property features, creative control of storm water and utilization of predominantly native plants promote the development of sustainable landscape environments, mutually beneficial for both people and nature.

Eric also specializes in an environmentally appropriate approach to the integration of exotic and tropical plants into indigenous landscapes.

Memberships and Awards:

• Member; American Society of Landscape Architects
• Member; Brandywine Valley Association
• Philadelphia Flower Show, Best in Show, Educational Exhibit, Zoological Society of Philadelphia, ‘Where Eagles Soar’
• Pennsylvania Horticultural Society 2005

• Design Show Home 2002
• Philadelphia Magazine, May 2002
• Merit award for a Built Project: DuPont Chestnut Run Plaza
• American Society of Landscape Architects PA/DE Chapter 1993
• Merit award for a Built Project: The Villages at Creekside
• American Society of Landscape Architects PA/DE Chapter 1993
• SAM Merit award for Best Landscape Design Detached Model Complex: Princeton Landing
• New Jersey Builders Association 1993
• Achievement in Planning Excellence (APEX) award: Pohatcong Village
• New Jersey Builders Association 1991

Jason Gehman

Project Engineer

Jason joined Wallace Landscape Associates in April of 2021 as a Project Engineer. He received a Bachelor of Science in Civil Engineering with a concentration in Project Management from Drexel University in 2020.

Jason’s background in project management, along with his previous experience in landscape construction, led him to his current position as project engineer. Jason oversees daily construction and planting operations including scheduling logistics, troubleshooting, and project coordination and management.

Jason enjoys being outdoors overseeing jobsites, but also enjoys researching and finding opportunities to enhance the workplace with the latest technologies. He utilizes his understanding of technology to create a more efficient work environment and help keep Wallace ahead of the curve. Incorporating new technology, and a highly organized system, are key to him keeping construction projects running smoothly and Wallace clients happy.

Thomas Darlington

Landscape Designer

Thomas joined Wallace Landscape Associates in March 2025 as a Landscape Designer. A proud graduate of Penn State’s Stuckeman School of Arts and Architecture, he holds a degree in Landscape Architecture.

With a diverse background spanning landscaping, greenhouse operations, land development, and design practices, Thomas brings both technical expertise and creative vision to the team. He is passionate about integrating technology into design and is highly skilled in Adobe Creative Suite and Autodesk software.

At Wallace, Thomas collaborates closely with designers and construction managers to transform complex landscape concepts into detailed blueprints and dynamic digital renderings for client presentations. His ability to merge artistry with precision helps bring each project to life from concept to completion.

Outside of work, Thomas enjoys spending time outdoors and supporting his family’s multigenerational farm. His personal interests include disc golf, camping, Dutch oven cooking, and nature photography—pursuits that reflect his deep appreciation for the natural world.

Julia StreetT, PCH

Maintenance Manager

Julia Streett joined Wallace Landscape Associates in the winter of 2022, beginning her journey as a gardener and quickly developing strong relationships with clients and the landscapes of southeastern Pennsylvania. In the fall of 2023, she was promoted to Garden Maintenance Manager. In this role, Julia works closely with designers and clients to create customized management plans and strategies that ensure gardens remain healthy and vibrant year-round. Her dedication to environmental responsibility is evident in her preference for native plants, organic materials, and sustainable landscape practices.

Julia holds a Bachelor of Science degree in Environmental Science and Marine Geology, a foundation that has given her a holistic perspective on the natural world. Her early work across public lands along the East Coast and in Alaska deepened her appreciation for the essential role plants play in human environments. Today, she remains committed to making outdoor spaces both beautiful and accessible for all.

Outside of her work at Wallace, Julia can often be found tending to her own garden, where she enjoys the company of her dog and the tranquility of her beloved frog pond. She takes pride in every project she manages and is continually exploring best practices in garden care. Julia is also a trusted educational resource, sharing her knowledge generously with both clients and the Wallace gardening teams.