Co-organiser Kelly Aitcheson said the free party was "awesome'' last year and was primed to be "even better'' this year.
More of Peter Johnstone Park would be used to hold the party this year and more entertainment would be on offer in the carnival area, she said.
The success of the event last year had given the carnival area operators the confidence to bring a bigger operation this year, Ms Aitcheson said.
"I told them to bring their A game.''
About 70 craft and retailer stalls would be operating, she said.
More than 10 food trucks were expected.
Party co-organiser Regan Horrell said several talented local musicians - including a solo performer, a band and a children's entertainer - would perform chilled music at the celebration.
The party runs between 10am and 3pm.
The event starts the Festival of the Plain celebrations, which includes a Mosgiel-Taieri Community Board's Tidy the Taieri campaign and ends with a family fun day at Wal's Plant and Fun Land next Sunday.
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