The 10th annual reception of the All-Party Parliamentary Gardening & Horticulture Group (APPGHG) brought together more than 100 representatives from across the industry with parliamentarians on Monday 23 November.
Benn applauded the group for its commitment, saying: "I want to congratulate you on being an extremely well-organised lobby group. You do an outstanding job."
High on the agenda was the issue of research and the frustration among industry over a lack of proper consultation by the University of Warwick over the future of HRI Wellesbourne, to be amalgamated with biological sciences in a single school of life sciences.
HW editor Kate Lowe thanked the APPGHG for its support of the horticulture industry and HW's Save Our Science campaign.
Addressing the 130-strong crowd, she asked the secretary of state to consider a proposal to match-fund the levy for research and highlighted the need to recognise the "key role" that green planting has to play in challenges such as air quality and storm-water management.
She also asked Benn "to apply pressure for a proper consultation on Wellesbourne".
Scotts managing director Martin Breddy highlighted the progress industry had made on peat reduction. He said: "I hope you agree that collaboration is the way to approach these issues."
With the Cumbrian floods fresh in his mind, Benn echoed points raised about horticulture's role in adapting to climate change, in particular the crucial role of trees.
"We know trees will be fundamental in dealing with the threats," he said. He was due to back an independent assessment of trees and climate change this week.
On R&D, Benn added that the new Technology Strategy Board Innovation Platform in Agriculture & Food, with its £13m crop protection R&D fund, could provide a major benefit for the industry. "The way to test the system is to get the bids in, otherwise there is no chance of getting the money at all," he warned.
TV gardener Alan Titchmarsh also spoke at the event, along with APPGHG chairman Ann Cryer and secretary Brian Donohoe.
City of London joined the group as a new sponsor, along with BALI, Scotts, Royal Parks, the HTA and HW.