About 100 current and ex-students and staff are to gather at the Guildford college to mark the anniversary on 1 November and review how the sector has evolved since 1972, said head of the landscape department Tony Begg.
"We were the first college in Europe to start that sort of course," said Begg, who was at the college for the inaugural course. "We will look at how the industry has changed over the years. In some ways it's altered dramatically, in others not at all.
"In those days we were talking about the need for formal career progression and a skills framework before the profession was a household name. We are still calling for them."
Speakers will include college old-boy David Dodd, who recently worked with David Domoney on the TV show Love Your Garden, and Lantra's David Winn, who will talk about the latest steps to enshrine an industry-driven skills framework.
BALI chief operations officer Wayne Grills will give a wider industry overview. Email firstname.lastname@example.org.