Any traceability/tracking system requires some type of labeling or identifiers to be attached on or around the items in question. These can be Barcodes, Stickers, NFC, RFID or any number of other options for tagging physical objects.
In Washington State specifically we are using 16 digit identifiers issued by the State. The State supplied system provides a printed label that includes a C128B barcode as well. The generated documents are PDFs designed to print on small single-shot label printers like a Zebra or Dymo. We'll evaluate costs from this viewpoint.
The Dymo printers cost between $50 and $250. A really good one (450 Turbo) is on Amazon for about $70. Label rolls can be purchased too, about $16 for two rolls of 350.
So, about $70 for the printer and about $0.022/label.
The most commonly recommended printer for seed-to-sale software vendors is the Zebra LP 2824. This printer retails on Amazon for about $250. Labels cost about $42 for a pack of 12 rolls, 100 labels per roll.
About $250 for the printer which prints about $0.0035/label.
Another option is to use a generic laser printer and Avery (or compatible) labels. If you don't have a laser printer one can be had for about $100 from any office supply store. A box of 3000 labels of the Avery 5160 size can be had for $21 for a cost of 0.007/label.
This is a newer technology, it would require some custom hardware to fully implement in your operation but offers higher levels of automation than standard labeling. The NFC Tags which would be affixed to inventory items can cost as high as $1.00 each; but buying in volume it's possible to get the per tag cost below $0.35
The RFID standard has been adopted in many other inventory control situations and it's well suited for the operations that want high levels of automation, like what is available via NFC. Like NFC, the RFID tags require special hardware to read which adds an additional cost. Printable tags, compatible with Zebra printers which contain RFID tags can be purchased for about $0.186/tag; clip on tags can be had for around $0.361/tag.
Plants and inventory must be physically tagged and include the State required data. Multiple options exist from common hardware and low-cost labels. More automation is available if using a labeling solution with a higher per label cost. Using the values provided here and some of your own research you should be able to make the cost-benefit judgement for your business.