Chrysanthemums genetically engineered to produce blue flowers cannot be freely imported into the U.S. and traded as non-regulated crops under a new USDA decision.

Most requests for non-regulated status for genetically-altered crops in recent years have met with approval from the agency’s Animal Plant Health Inspection Service, so the recent rejection of Suntory Flowers Limited’s application to import cut flowers is rare.

Unlike many of the crops determined not to fall under regulations for genetic engineering, the blue chrysanthemums were “clearly regulated articles as they were engineered using plant pest sequences,” said Rick Coker, public affairs specialist with APHIS.

Crops that are gene-edited to remove or alter genes without inserting foreign DNA from plant pests don’t come under USDA’s biotech authority.

The agency has allowed for the importation of two genetically engineered cut flowers and one fruit under its jurisdiction — baby’s breath, roses and pineapples — because the possibility for propagation in the U.S. was remote, Coker said.

“Put another way, the data suggest that if you were to take all four of these and throw them on top of a compost pile, the only one capable of propagation is the chrysanthemum,” he said in an email.

While the chrysanthemums in question would be sold as cut flowers, the plant is also a common nursery crop in the U.S., with about $200 million in sales of potted chrysanthemums a year, according to USDA data.

Coker said the timing of Suntory’s inquiry was “unfortunate” because APHIS is currently considering revised rules for biotechnology under which the blue chrysanthemums “almost certainly would not be regulated.”

Suntory, which is based in Japan, is still deliberating the USDA’s response, including its offer to consider additional information that could alleviate the agency’s concerns, said Cory Sanchez, the company’s representative in the U.S.

“They did leave the door open for us,” he said.

It would still technically be possible to import the cut blue chrysanthemum flowers into the U.S. as regulated biotech articles, but this would requiring filing a 180-day notice before every shipment, he said.

State governments could also impose their own conditions on the cut flower shipments, complicating their transport, Sanchez said.

“That would be really difficult to do,” he said. “It’s not even worth doing business that way.”

The Center for Food Safety, which has criticized USDA’s biotech regulations, wonders whether the agency’s approach to the chrysanthemums was influenced by genetically engineered petunias, which were imported into the U.S. last year without federal permission.

The agency may have realized that flowers with novel colors are “irresistible” to many enthusiasts, who could then sell pirated versions of the cultivars while violating intellectual property laws, said Marti Crouch, consulting scientist for the group.

In reality, genetically engineered baby’s breath, roses and pineapples were also at risk of propagation, she said. “In all those cases, an enterprising horticulturist could propagate the plant.”

Despite the USDA’s rejection of Suntory’s request, the Center for Food Safety is not reassured the agency will be stricter in its scrutiny of potentially non-regulated crops, said Bill Freese, science policy analyst for the group.

“We’re concerned in general about the effort to eliminate the regulation of more and more crops,” he said.