The festival - at Powderham Castle in Exeter, Devon, on 2-3 May 2014 - will host more than 100 stalls, featuring specialist plant nurseries, garden machinery, tool manufacturers and seed merchants.
Buckland said: "Feedback from local growers and friends within the RHS is that a West Country garden show with easy access from the M5 is long overdue.
"The demographic includes a large population of active, retired gardeners who spend a lot of time and money on their gardens. That's coupled with an infrastructure designed to cope with an influx of tourists who need little persuasion to come and make the most of our mild springtime climate."
Speakers at the festival include Buckland and Cleeve Nursery's Alan Down. For details, email firstname.lastname@example.org.