Alistair Baldwin will take charge of the design and masterplanning arm of the practice and securing new business in heritage leisure, private estates and public gardens.
He joined the Landscape Agency in May 2007 after 10 years as senior lecturer in landscape architecture and garden design at Leeds Metropolitan University.
In 2006 Baldwin received the university's Chancellor's Award for Outstanding Contribution to Teaching and Learning.
Since joining the practice, which has offices in York, Warwick and London, Baldwin has secured a major commission from the RHS to work up masterplans for gardens at Harlow Carr, Hyde Hall, Rosemoor, and Wisley.
Phase one of the masterplans was completed earlier this year.