Delays in the delivery of specially-made paving for the main space has forced the opening of the Thame Youth Memorial Garden to be postponed.
The opening ceremony was originally due to happen on September 8, but will now be on September 29.
The ceremony will start at midday and refreshments will be served from 1pm in Christchurch, Upper High Street.
An 80s themed disco night is being held on Friday (September 6) to raise money for the youth memorial.
The fundraiser will be at the Spread Eagle in Thame from 7pm.