She was one of only five people - and the only one from outside the US - invited to take part in the workshop at the Institute of Floristry in Minneapolis, where she learned her craft.
Participants were paired with a master floral designer and each morning given themes to work with.
In MasterChef style, they were given five minutes to choose more flowers or other things to fit with the theme.
They then had three hours to create five designs before presenting them to the group.
Unlike MasterChef, no-one was eliminated.
Their designs were also subjected to a photo shoot for a magazine which will depict the trends and themes for the coming year and be distributed to those in the floral industry.
She said some of those trends were millennial zest - bright colours, vibrant patterns and adventurous compositions; eco vogue - all things green; early birds - anything involving birds; global connoisseur - flowers with vintage or new maps, stamps and intriguing or exotic finds.
But her time at the workshop was not solely about flowers.
"One night we sat down with Cromwell wine ... [I was] sitting down with these people from Hollywood, Europe, New York, everywhere, and talking about Cromwell and drinking Cromwell wine," Ms Wilson-Thiel said.
The trip gave also gave Ms Wilson-Thiel the chance to visit her husband, Darrel Thiel, for a short time.
Mr Thiel, a retired American soldier, spends the New Zealand winters in the United States with his children and grandchildren.
