Her daughter, Rachael Pedersen, who is a textile and fashion technology teacher at Whangarei Girls' High School, encouraged her to enter.
"It's a role reversal. Usually you're inspired by your mum, I'm inspired by my daughter."
Her design was based around the beautiful red, fluffy nurses capes from the war era.
"I really admired the design of it, the practicality of it."
Mrs Smith said the New Zealand nurses were subject to strict authority and she used a leather belt which went around the neck, down the back and front and around the middle to represent the discipline.
The skirt has see-through style pockets in it, which Mrs Smith said people can put things in to make the garment their own.
Her entry was modelled by sisters Lucy Duff and Jess McPherson. One was wearing the finished garment and the second was dressed as the pattern.
"I wrote all over it so people could see the thinking.
"I guess because I came from a teaching background I wanted it to be a teaching moment."
Mrs Smith was surprised when she was announced the overall winner.
"I was stunned, and very gratified. Everything came together and the judges got it."
She said the garment was a year in the making, but most of that time was thinking, planning and editing.
Mrs Smith's prize was a special edition Bernina sewing machine, the first one to make its way into Northland. She also won the Open Street Wear category and took home $400.
In other awards, Megan King and her Reck'lace' in Red entry won the Ruby Red category and the Extreme Elegance award.
Celina Yang won the Northland's Top Model award and Erin Ward won the First Time Entrant award.
Lauren Thomsen won the Student Fashion Design category and Sarah White won the Student Street Wear category.
The Masquerade category was won by Rachael Jackson and the Trash to Fashion category was taken out by Taylor Botha.
In the wearable art categories, Luka Danvers won the junior award, Kaylee Tantrum the student award and Alarnya Ashby the open award.
Steam Punk was won by Tori Ward.
Whangarei Girls High School were judged best school and the Rotary Club of Whangarei South donated a new sewing machine.
A collection of the entries are on display at Bernina Northland and an exhibition of garments will open at Kiwi North next month.