They are predicting approximately 1,200 visitors, almost double last year's 564.
And this year's exhibitor numbers have already exceeded 2008's, with 90 companies signed up with six weeks still to go before the show on 7 October at The Matford Centre in Exeter, Devon.
Chairman of the show committee Mark Taylor said: "Not only have we had a real positive response to our pre-registration literature, we are delighted to announce that the calibre of those who have registered as visitors is extremely high."
Show representative Clive Marlow said that many of the major plant buyers had already registered and that there had been a good response from local authorities too.
Devizes Town Council from Wiltshire are among those visiting for the first time. It is currently redesigning its main park, which will include greenhouses and growing facilities.
Other key exhibitors include Avoncrop, Delamore, Kermock Park Plants, Moles Seeds, Pentland Plants, Quinton Edwards, Seiont Nurseries, Tendercare Nurseries, Thompson & Morgan, Whetman Pinks and Young Plants.
Entry to the show is free. To find out more visit www.southwestgrowersshow.co.uk or call 01684 576427.
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