Duchess Kate bowls them over with NZ clover

The Duchess of Cambridge attaches a sprig of shamrock to Conmeal, an Irish Wolfhound, the mascot of The Irish Guards, as she attends the St Patrick's Day Parade at the Mons Barracks in England. Photo / AP

Kate Middleton got into the spirit of St Patrick's Day in a New Zealand designer's elegant green dress coat at a parade at the weekend.

But the excitement was too much for three soldiers who fainted in their stiff red uniforms under the weight of their bearskins.

Kate's glamorous attire was a creation by Auckland-born designer Emilia Wickstead who is now based in London.

The Duchess of Cambridge, 30, bought the green belted coat dress especially for the occasion and accessorised with a chocolate brown hat by Lock & Co and brown suede heels, the Telegraph reported.

She also wore a gold shamrock brooch by Cartier, a royal heirloom first worn by Queen Alexandra in 1901 and which has also been worn by Queen Elizabeth the Queen Mother.

The Duchess watched the ceremonial military parade with a smile before bestowing three-leafed clovers on 40 officers.

But as the Duchess arrived at the Mons Barracks in Aldershot, Hants, home to the 1st Battalion Irish Guards, three soldiers fainted.

Stretchers were brought out before the men were helped to their feet and staggered off the parade square.

While it was the first time Kate wore a creation by Wickstead, the Kiwi designer has had a royal connection for some time.

She dressed a handful of guests for last year's Royal Wedding, including Kate's cousin Lucy, Lady Kitty Spencer and Emma Parker Bowles.

Wickstead was born in Auckland, and lived in New Zealand until she was 14, when she followed her mother, Angela, to Milan.

Later on, she moved to London to study fashion design and marketing at London's Central Saint Martins whose graduates include Alexander McQueen and Stella McCartney.

Wickstead then moved to New York where she spent time working at various fashion houses and at US Vogue before launching her label in 2008.