More than 1,000 visitors pre-registered for the event, with 300 arriving in the first hour. HTA director-general David Gwyther said he was delighted with the industry's response.
"We are really pleased at the way it has come together. It is important that this is happening now - the industry had a very good year last year and a not bad one this year but we are seeing dark clouds on the horizon. The move in the sterling/euro exchange rate combined with economic and social pressures will put pressure on the market.
"That means the industry absolutely must work together by removing some of the unnecessary costs of doing business. This event shows we can do that without spending huge amounts of money."
Gwyther said the HTA was focused on tackling supply chain problems by fostering closer collaboration and would be looking at issues including distribution. HTA business development director Tim Briercliffe, the driving force behind the event, said it would help improve supply chain collaboration.
"There is a great feeling here and it's really good to see everybody working together - there is such a positive buzz around the place," he said. "There was a lag period on the exchange rate so even though it has been in our favour for some time, it's only this year that we have seen a lot of garden centres using more British suppliers, so hopefully they won't rush back to imports."
HTA president Caroline Owen added: "Plants are what set us apart so it is important to have a show at this time of year because this is when plants are looking great." Exhibitors agreed and praised the show's plant focus and end of season timing.
Oakover Nurseries general manager Brian Fraser said: "It's a very good idea having just a plant show. There seems to be a huge amount of interest because it's the first real show of its kind. The exchange rate and what public spending cuts happen are very interesting for us so the timing is useful."
Hillier Nurseries managing director Andy McIndoe agreed: "It's very good at this time of year, while the season is still very much in the mind. The thing I have been very pleased to see is people bothering to bring their whole team along."
Osberton Nursery director William Murch added: "We're very pleased to come to the show. Lots of the garden centres that we deal with are here who haven't been to other shows for a while. The proof in the pudding will come next year to see whether people come back a second time."
Kings Seeds commercial development manager Ian Riggs, visiting the show, said he was impressed that so many growers made the effort to attend, given the event's timing. "People have been very busy so this is probably the first time they can get off the nursery. It must have been a real dilemma whether or not to come."