The levy is a federal tax levy to be applied to the container (plastic, ceramic, natural or other, i.e., bag, pot, seedling tray/punnet) which is used by the producer. 

The nursery and garden industry levy program is facilitated by Hort Innovation in partnership with Greenlife Industry Australia (GIA). It is funded by the nursery products R&D and marketing levy as well as voluntary contributions from industry. The Australian government provides matched funding for all Hort Innovation's R&D activities.

In collaboration with GIA and the state nursery and garden associations, Hort Innovation helps businesses in the nursery and garden industry by investing the nursery products levy in targeted marketing and R&D programs. Priorities for this investment follow the objectives of the Nursery Industry Strategic Investment Plan 2022 - 2026

Read more at:
Australian Government Department of Agriculture
Your Levy at Work and GIA.

Levies Revenue Service (LRS)

There are two documents currently available for nurseries regarding the Levies Revenue Service and the system/structure for the nursery and garden industry:

LRS — Return of Nursery Products