Exports were stalled in September following the discovery of light brown apple moths in a container of flowers grown outdoors in the South Island.
New Zealand Paeony Society president Rodger Whitson, of Wingatui, said the timing was good for Otago and Southland growers, whose crops have been delayed a little by cool weather.
Those further north in Nelson, Marlborough and part of Canterbury had been picking for two weeks and unable to export to the US.
The Ministry of Agriculture and Forestry Biosecurity New Zealand (MaFBNZ) section negotiated with the United States Department of Agriculture and a compliance programme was worked out.
It is based on a spray programme to prevent infestation of the crop by the moth and involves properties and packing sheds being inspected and registered by MaFBNZ as complying with the approved programme.
Mr Whitson said it would cost growers between $1000 and $2000 to comply.
Omeo Peonies owners Judy and Tony Banks, of Earnscleugh, said word came through on Thursday that if certain criteria were met, the exports could proceed.
An inspector visited Omeo Peonies on Wednesday and took leaf samples for analysis to prove that the chemical had been applied.
"Despite the fact that our livelihood depends on having a clean crop, they don't take our word for it," Mr Banks said.
"Orchids got the OK within a few weeks of the ban as they are grown in glasshouses and therefore infestation can be prevented, but other flowers [hydrangeas and calla lilies being the main ones] are still waiting."
Mr Banks said they just had to wait for property and packhouse registration, which hopefully they would have within 10 days, and then they could start exporting to the US.
"People in Nelson have already been picking for a fortnight and have had trouble finding markets for their early varieties.
We've been lucky as it has been quite cool and we're just starting to pick now," he said.
Mr Whitson said he had picked the first bloom on his property this week, but did not expect to be in full swing until the end of next week.
His picking season was about six weeks long, but in warmer places it was often shorter.
He was hopeful that the market would be buoyant following the US presidential election and with the Thanksgiving holiday only weeks away.
There had been a "wee bit of negativity" among growers about the new requirements, and it had been hectic trying to get them introduced quickly, but he considered it would be good for the industry in the long run.
The controls would mean everybody would be in line as far as spraying was concerned and helping to keep pests out of other countries.
