Each member garden centre will be assessed by an inspector across all departments and awarded an overall score. Centres must achieve 60 per cent or above to remain as members.
GCA chairman Peter Burks said:
"The annual inspections, which take place from March 26 until June 15, begin with an assessment from an independent inspector.
"Once the inspection is complete, the inspector will discuss their findings with the garden centre owners, managers and staff in a constructive feedback session. This allows management to implement any necessary changes, based on the inspection findings, immediately.
"Many GCA members have said that the unique annual inspections and constructive feedback sessions are one of the biggest benefits of membership. It is a fantastic motivational and management tool and really keeps staff on their toes, making sure they are always doing their absolute best.
"Garden centres receive no advance warning about when their inspection will take place and they do not have the option to turn away the inspector. It is all about making sure they are offering a consistently excellent service and improving their customer service standards, which is what all GCA garden centres must do to remain members."
"This year we have split up merchandising and display on the score sheet. We are hoping that this will encourage members to try and create more inspirational displays. I would advise members that displays do not have to be huge to have an impact.
"We have also increased the weighting of the environmental section, in order to promote best practice in environmental care.
"We believe all members should be doing everything they can to be green and hopefully this will act as an incentive for them to go the extra mile and put some careful consideration into their current environmental policies."
The GCA represents nearly 200 garden centres nationwide.