Young IOG board of directors' chair John Ledwidge told the event that some apprenticeships in the industry were poor - but that there are examples of good schemes too:
"Budgets are being cut and we have a double-edged sword: some apprenticeships are a bit like slave labour; they're cheap. You can look at it two ways; it's taking people away from the industry. But it's also a way of bringing others in and training them up properly. There are lots of good schemes, such as ours and they are a good option."
Ledwidge, head groundsman at Coventry City FC, said most people inherited, fell into or were born into the job.
To help counter this and attract 14 to 25 year olds the board was working on a £43,500 project largely funded by the HLF.
"We wanted 14 to 19 year olds engaged in what we do and secured a grant to deliver this over 18 months," to be used on a range of things such as developing learning packages, a framework and strategy.
On apprentices he said: "As a profession we need to sing from the same hymn sheet. We often find inconsistencies: people criticising without offering solutions. Everybody needs to be united and it needs to come from us as well as higher up."
Olympic Park landscape chief Mark Camley said: "We are looking at bringing in apprentices, which I did at the royal parks and was proud to do so."
IoG chief executive Geoff Webb said: "We need to do more on training and education to encourage the next generation into this career. We are looking at 14 to 19 year olds but beyond that as well."