Passenger Baggage:
Importers may bring in up to 12 soil-free plants and seeds of herbaceous plants that are not subject to prohibition or special requirements such as a permit, treatment, or ESA or CITES documentation.
To import more than 12 plants, an importer must have a written permit and the plants must enter the United States at a port with a USDA plant inspection station. All quantities of plants or seeds must be accompanied by a phytosanitary certificate from the exporting country unless the importer has been granted a USDA import permit exempting such documentation.
Port of Entry and Inspection:
All plants and seeds must be inspected and must include Phytosanitary Certificates except as noted above (e.g. small seed lots with PPQ 587). It is recommended that if importing more than 12 plants in Passenger Baggage that you call before your trip to make arrangements with the inspection station at the port of entry (see list linked below for contact information). Otherwise the plants and seed will be inspected by a regular Customs Agent.
List of Plant Inspection Stations
http://www.aphis.usda.gov/import_export/plants/plant_imports/plant_inspection_stations.shtml
CITES (note specific Port for Dionaea)
http://www.aphis.usda.gov/import_export/plants/plant_imports/downloads/list.pdf
Specific Regulations
http://ecfr.gpoaccess.gov/cgi/t/tex...div8&view=text&node=7:5.1.1.1.6.8.36.5&idno=7
(e) Any restricted article not designated in paragraph (a) of this section may be imported or offered for importation into the United States only after issuance of an oral permit for importation issued by an inspector at the port of entry.
(f) An oral permit for importation of an article shall be issued at a port of entry by an inspector only if all applicable requirements of this subpart are met, such article is eligible to be imported under an oral permit, and an inspector at the port of entry determines that no measures pursuant to section 414 of the Plant Protection Act (7 U.S.C. 7714) are necessary with respect to such article.