Unusually for the library, audiences are encouraged to bring along drinks and snacks.
"It's nearly three and a half hours of poetry, but we can't allow alcohol," Tracy said.
Poets Alive member Sue Edmonds said it was a diverse range of people who attended the event.
"They just come out of the woodwork," she said.
The poetry slam will start with the junior class (12-17 years) with the open class following on.
Tracy said adult languages and themes should be expected from the slam poetry performances.
If you would like to perform, the open mic is open to entrants on the day, but for slam performances booking is essential.
"The open mic has performers on for about two or three minutes, and we want to give everyone a chance where there's a safe and encouraging audience," she said.
The event is co-hosted with with Poets Alive and Te Ahu Rei.