From the USDA 1/25/18:
"At its Fall 2017 public meeting, the National Organic Standards Board (NOSB) heard significant testimony about hydroponic, aquaponic, and aeroponic operations. Given the extensive debate on this topic, the Agricultural Marketing Service (AMS) is posting this notice to clarify the status of these systems.
"Certification of hydroponic, aquaponic, and aeroponic operations is allowed under the USDA organic regulations, and has been since the National Organic Program began. For these products to be labeled as organic, the operation must be certified by a USDA-accredited certifying agent, and maintain compliance with the USDA organic regulations.
"The NOSB has recommended prohibiting aeroponic systems in organic production. USDA will consider this recommendation; aeroponics remains allowed during this review."