The newly named Plant Fest will be held on 15 and 16 September and will break with previous trolley fairs held by the company in that customers will be able to take home all stock on the day.
Managing director Alan Beaumont explained: "Because of what's happening in the economy - and by September we should know a bit more about the cuts - there could be some difficulty in the market by then. Already when you talk to retailers they report a reluctance on the part of customers on discretionary spending.
"We felt the September event could be better because we found buyers were picking the stock they wanted and then reducing it down to a budget. Our research has shown that this (new) format might be better for buyers and should help inspire them."
The event will be marketed along three key lines - great plants, strong savings (150 different promotions) and exclusive varieties. Under the regular format, growers' lines were presented on the day by Greenfingers, which takes commission on each trolley sold and delivered at a later date. But the company's own lines were available to take home on the day.
With the new format, Greenfingers will buy all of the stock prior to the event, meaning that it is all available on the day.
Beaumont added: "There will be in excess of £1 million of stock up for grabs. I am visiting UK, Dutch and Italian nurseries in the next few weeks to make sure that we have some new and unusual varieties." The spring trolley fairs will take place as normal.