Later, in a sombre ceremony, they will be laid on the steps of Victoria's Parliament House.

As millions of  barbecues sizzle across the nation, they will commemorate Invasion Day – the first day of their colonisation.

"We don't want to celebrate the genocide of our people, and this is what celebrating Australia Day represents for us," said Meriki Onus, the commemoration's organiser.

"So we're going to have a memorial tomorrow to remember all those people who fell victim to the genocidal act by the Australian state."

Onus will lead a smoking ceremony at 10am at Tianjin Gardens, near the corner of Spring and Little Bourke streets. A rally will be held on Victorian Parliament steps at 10.45, and the wreaths will be laid. Those present will then march with home-made protest banners through the city to Birrarung Marr.

Those wishing to participate are encouraged to bring their own flowers, which will be laid beside the wreaths.

Onus, 27, wants Australians celebrating to remember that for her people the wounds of invasion are as raw as ever.

"The conversations that normally I have with people are 'why can't you just get over it', or 'yeah but it happened a long time ago'.

"Actually, no, we have the highest youth suicide rate in the world, Aboriginal people.

"This is not in the past, this is not something that we have to get over. We're still being affected."