Owners and staff at nearly 200 garden centres across the UK will soon receive a visit from a GCA inspector to assess whether they are meeting the strict standards of membership.
The annual inspections are currently underway and will run until June 15, assessing each business across departments and awarding a final score which must be above 60% in order to retain membership.
GCA chairman Peter Burks said: "Once the inspection is complete, the inspector will discuess 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."
Mr Burks added that many member garden centres see the inspections as "a fantastic motivational tool" to keep staff on their toes.
The garden centres receive no advance warning about when their inspection will take place and do not have the option to turn away the inspector.
"It's 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," said Mr Burks.
The scoring system has been changed for the 2012 inspections, splitting up merchandising and display. Mr Burks explained: "We are hoping that this will encourage members to try and create more inspirational displays."
The environmental section has also been changed to carry more weight and promote green efforts.
GCA chief executive Phil Slinger said: "Last year several garden centres were not ready and lost marks, which of course meant they will have also lost sales, because increased standards and motivated staff results in increased sales and profits.
"The results of the inspections form the basis for many GCA awards ... Any centres scoring 86% or above will also receive a Garden Centre of Excellence Award. We'd like to wish everyone the best of luck. GCA garden centres have such high standards and we are looking forward to seeing the ideas people have come up with this year to further improve these."