Helpers from schools, companies and community groups will gather at a 60-hectare plot in Whiteman Park to break the world record for most trees planted simultaneously.
The current record is held in the Leh region of India, where 10,000 people gathered in 2012 to plant 99,300 trees in an hour.
A total of 100,000 or more trees will need to be planted within an hour for the feat to be achieved and to set a new record.
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READ NOWPlanting kicks off at 12pm, which is also National Schools Tree Day.