Running over two days on Tuesday, May 4 and Wednesday, May 5 the festival is a celebration of two of Japan's annual public holidays, Greenery Day and Children's Day.

A feature of the Koyo Festival will be the inauguration of an annual oration aimed at understanding the unique blending of Japan and Australia represented by the garden.

Dr Peter Armstrong, the 2021 lecturer, has deep experience with Japanese culture, a lifelong passion that began with studies at Waseba University in the early 1970s before returning to Australia to practice architecture.

He is also no stranger to Cowra, bringing to many Cherry Blossom Festivals at the Garden demonstrations by the Australian Sumo Federation.

In more recent years, he has been a serious student of tea ceremony, which he will assist in demonstrating with other members of Urasenke Sydney.

"'My student experience in the 1970s was a life-changing one," Dr Armstrong said.

"It was a time of building future bridges across national borders, and it was in this decade that the idea of the Cowra Japanese Garden and Cultural Centre took shape and became a reality.

"It was the culmination of the efforts of so many Cowra people in the decades after the Second World War to foster friendship between the people of Japan and of Australia," he said.

An Honorary Associate Professor in the University of Sydney's School of Architecture, Design and Planning, Dr Armstrong hopes the autumn festival and the beginnings of an annual lecture series will bring greater appreciation of the historical significance of Cowra's success in post-war reconciliation efforts.

Cowra Japanese Garden manager Shane Budge said the idea of the Autumn Festival sprang from the COVID-19 pandemic.

"We got a lot of support during the pandemic and as a way of thanking people for that support we wanted to do an event where we could say thanks to everyone who donated and helped us through the shutdown period," Mr Budge said.

"We already have Sakura in springtime, this festival is a bit different in it is more focused on the cultural centre with an educational component, especially for children.

"We'd like to start promoting more educational opportunities for children at the garden and it just so happened we were lucky enough to get a community heritage grant which gave us more focus on our cultural collection.

"So we blended our wish to say thanks with the cultural collection and came up with the idea of the Autumn festival.

"It coincides with Children's Day and Greenery Day, a week of annual holidays in Japan, that's why it is on Tuesday and Wednesday, to reflect what is happening in Japan.

"It made sense to have Greenery Day which is more about the garden and the collection at the cultural centre and Children's Day focussing on the kids."

Mr Budge hopes Cowra's school will become more involved in the festival, if not this year, in future years.

"We have some children from Cowra Public coming which is great," Mr Budge said.

Up to 160 children from KInder to Year 2 are expected to visit the Japanese Garden on Children's Day.