Management Team Bios

Sean Cashman, President

Sean Cashman founded Cashman Landscape Management and Design Inc., in 1996 with a simple philosophy – to provide a quality product at a fair price.  Sean started in the Green Industry in 1987, working for a high end residential and commercial landscape management firm. Quickly running through the ranks Mr. Cashman, a passionate individual, could not be held to just working “for” someone. He needed to control his own destiny, beginning over 20 years ago, Sean started with 1 employee and went from running a mower to running a crew to running multiple crews to running a corporation –this experience is the cornerstone upon which Cashman Landscape Management and Design has been built.  Today, Sean is responsible for overall operations of each division, sales and corporate development.   Cashman Landscape Management has come to be known for its quality workmanship and ethical standards, which can be directly attributed to its founder.  As Cashman Landscape Management enters our third decade of service, Sean will continue to lead the vision first started in 1996 with his first truck and trailer.  Mr. Cashman holds a Bachelor of Arts degree from Seton Hall University.

Sean puts a great a great deal of time into his companies, however more importantly when he gets time, he loves playing tennis and golf. His passion overall is spending time with his two children whether its coaching, relaxing at the beach in LBI or just enjoying times at his home in Denville.


Aaron Van Duyne, Director of Sales and Construction Developement

For nearly 20 years, Aaron has been thriving in the landscape design build field creating and constructing one of a kind landscapes throughout the tri-state area. Currently, Aaron’s role as Director of Sales and Construction Development at Cashman Landscape Management and Design has allowed him the opportunity to manage and oversee a team of talented designers and project managers whose goal is to create high end, award winning, residential landscapes in the most stylish, sophisticated, and original ways possible. Aaron manages all phases of the sales process, meets with clients to discuss their landscape goals and aspirations while helping them realize the potential of their property, and oversees the construction of the project from start to finish ensuring that all the client’s needs are met as well as exceeded. Aaron is considered a leader in the industry and regarded by many as the go to landscape professional for projects that require innovative and imaginative design, complex project management, and quality control. Aaron’s abilities to deliver these services has provided his clients with comfort and ease from start to finish. Educational accomplishments include a Bachelor of Science in Landscape Architecture from West Virginia University in 2005.

Prior to joining Cashman Landscape Management and Design, Aaron was given the opportunity to work as Landscape Designer for a luxury Hampton’s based landscape design/build firm.  During his time there, Aaron worked along side some of the world’s best Landscape Designers on some of the country’s most prominent properties.  Aaron treated this time as a great learning experience which helped strengthen his passion for his work.

Following his time in the Hamptons, Aaron returned to his home state of New Jersey where he was the Residential Department Head at an award-winning local landscape company.  His role was to design, manage and implement both small and large scale residential projects throughout New Jersey and New York City.

Aaron and his wife, Courtney, have two children, Aaron V and Emma Grace.  When Aaron is not hard at work, he enjoys spending time with his family and friends, boating, fishing, working on home improvements, traveling, hiking, and various sporting activities.


  • 2014 NJLCA Award of Distinction $50,000 – $100,000 Residential Projects
  • 2015 NJLCA Award of Distinction $50,000 – $100,000 Residential Projects
  • 2015 NJNLA Award of Superior Excellence in Residential Design


  • North Caldwell Magazine “Adding Color to your Landscape” May 2017


Ryan Sommers, Director Operations Green Horizon

Ryan Sommers joined the Cashman team in 2011, bringing over 20 years of experience in the green industry.   Mr. Sommers was previously a Branch Sales Manager and New Jersey State Licensed Pesticide Dealer for John Deere Landscapes.  Mr. Sommers now runs the operations, sales and corporate development for Green Horizon.  Mr. Sommers’ reputation and knowledge has helped bring Green Horizon into the forefront of the industry.  Mr. Sommers will continue to develop the lawn and plant health care company well into the future.

When Ryan isn’t impressing his clientele with his extreme knowledge of the green industry, he enjoys being on a lake or hiking through the trails of northern New Jersey with his wife and 2 dogs.


Susan Harcar, Office Manager

Susan joined the Cashman team in 2003, bringing over 15 years of management experience from wall streets commodity exchange.   Ms. Harcar controls all of the day to day office operations. Susan manages all of the billing and works closely with all accounting and book keeping with in the Cashman Companies.

When not working Susan has her husband Danny by her side and loves being at the beach in Wildwood and watching her two children Samantha and Carly take on the world.


Stafanie Stevens, Office Assistant

Stefanie joined the Cashman team in 2019, bringing over 15 years of management experience in the service industry.  Stefanie assists Susan with office related tasks. She manages most all daily incoming and outgoing communications for the Cashman and Green Horizon Brands.

Stefanie is highly proficient in our systems and when not working at Cashman enjoys teaching dance to children in the Sussex county area.