Members voted unanimously for GIMA to back Glee ahead of Garden Expo and members have subsequently agreed beneficial pricing for members exhibiting at the show.
GIMA director Neil Gow said members preferred the show's September timing, size, accessibility, facilities, heritage, expertise and focus.
He added that it was not true that GIMA's committee had pushed through the move, adding that one-third of the committee do not show at Glee.
Gow said only 48% of GIMA members showed at Glee in 2009 because Glee 2008 "did not meet expectations" but the show improved in 2009 and Gow hopes members exhibiting might rise from the 68 that showed in 2009 to nearer the 100-plus that showed in 2008.
He said individual companies would only get the same discounts as those GIMA can negotiate if they are very big after some companies claimed they could negotiate as big discounts as trade bodies by themselves.
He dismissed most of the shows that have eroded Glee's space from seven halls to three and visitor numbers from 25,000 to 15,000. Gow said Solex, a show for outdoor goods founded in 2008, "had a place", but new shows for 2010 Aqua and Garden Expo were unproven, while the new National Plant Show was "simply replacing the British Plant Fair". He said the many gift fairs "had been around for donkeys years".
He agreed these shows had taken exhibitors from Glee and that exhibitors were now showing common sense by booking smaller stand spaces.
Gow said the cost of shows is "irrelevant" (Glee is £200/sqm, 30% more than equivalent shows) and that quality of visitors was the most important issue.
He said the industry had to differentiate between cost and value and that Glee was providing more value than in the past. He said GIMA members wanted a "single focussed show".
But Gow added: "It is not in the interests of the industry to have one show because of the diversity of needs. One size does not fit all hence the specialised and focussed shows."
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