Most live plant imports require a USDA APHIS import permit and a phytosanitary certificate from the exporting country. Certain species or genera may be prohibited or restricted to specific ports of entry with inspection facilities. Some soil-grown material requires bare-root treatment before shipment. Importers should apply for APHIS permits well in advance, as processing times vary.

Cut flowers must enter through a port staffed with USDA APHIS agricultural inspectors. Many high-volume flower importers use designated air cargo facilities at major international airports. Shipments are inspected for regulated pests such as thrips and mites; infested consignments may be treated, re-exported, or destroyed. Pre-clearance programs exist for some origins and can speed release.