If you sell transplants for commercial use in NC, that means a farmer or anyone else in NC who intends to resell the transplants or the fruit, flowers, etc. produced from them, you must be inspected and you will probably need to be certified as a nursery. If you are selling to a local farmer within a 30 mile radius of where you produced the transplants and he/she has personal knowledge of the conditions under which they were grown, you are exempt from these rules.
If you intend to ship the transplants out of the state, you need to check the requirements of the importing state to determine if a certificate of inspection is required.
If you determine that your plants need to be inspected, you will probably need to get a nursery certificate, too. You will be certified as a REGISTERED nursery (less than one acre in size and does not sell outside the state) or as a CERTIFIED nursery (one or more acres in size or sells outside the state). It costs $20 per year to be a registered nursery and $100 or more per year to be a certified nursery.