Stanley, who will be part of a Garden Retail panel at Glee on 20 September asking whether garden centres are inspirational enough, said centres were losing their "edge" as an experience creator.
He will join BBC Gardeners' World magazine editor Adam Pasco and Scotsdales Garden Centre owner and HTA president Caroline Owen on the panel at Glee. Stanley said: "One of the major keys to success as an independent retailer is creating and maintaining an experience for the customer.
"Globally, garden centres were one of the key experience retailers. In the past two years the industry has lost that edge. The consumer is looking for 'social church' and is walking away from garden centres and being attracted to farmers' markets instead. This is a concern and an opportunity for garden centres that needs to be addressed."
Pasco has said garden centres need to drop their A-Z displays and modernise their merchandising. But many centre owners disagree, saying customers need familiarity to successfully use centres.
Are Garden Centres Inspirational Enough? will take place at the Glee hothouse seminar theatre, NEC Birmingham, at 9.30am on 20 September.
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