Speaking at the HTA Garden Futures conference last week, Gavin said designers should be challenged to be more innovative at the RHS Chelsea Flower Show.
"Designers don't do justice to Chelsea," he said. "We know that it's the same names coming up over and over again. Designers are getting lazy and they need to be challenged. We see the same gardens in the same shape year after year. We should be showing people something that's new, fun and exciting."
He warned that the UK's pre-eminent position in horticulture, gained from events such as Chelsea, could be lost. "Chelsea is a great thing, but somebody will come and take that trophy away from us. We should do better - the designers and the retailers and suppliers. Gardening is seen as conservative and we don't push it enough," he said.
Gavin added that his aim was to design meaningful gardens. "If I can design a few good gardens each year with soul - not just rolling things out but something that means something - I will be happy," he said. "We need to up our game, to stimulate and entertain."