A phytosanitary certificate issued by the national plant protection organization of the exporting country is required for virtually all live plant material. Many species also require an APHIS import permit obtained before shipment. APHIS may impose additional treatment requirements — such as cold treatment or fumigation — based on the pest-risk profile of the origin country and species.

Cut flowers (0603) are inspected for prohibited pests and diseases but generally move faster through clearance than rooted plants because they lack soil and are not propagating material. Rooted cuttings and potted plants (0602) face stricter scrutiny, including soil restrictions and, for some species, mandatory quarantine periods. Both categories still require phytosanitary certificates.