Mr McDermott stepped down from Farmers in October last year after 25 years at the business, and he and his wife retired to Tauranga.
Speaking to the Bay of Plenty Times Weekend from her Welcome Bay home yesterday, Mrs McDermott was still reeling from the tragedy.
"Rod was a good man, an honourable and godly man, who run the company with such integrity. He was good boss and a good man," she said.
Mrs McDermott was still finalising funeral arrangements and was too upset to comment further.
In a post on the Bay of Plenty Times' Facebook page Donnella Wellington wrote "Wonderful caring man. Cared about all his staff."
Mr McDermott was described as a "bit of an icon" in the retail sector by Chris Wilkinson, managing director of First Retail Group and led the company through some tough times.
David Norman, co-owner of Farmers through James Pascoe Group with his wife Anne, made an emotional tribute to Mr McDermott.
"Although it is six months since Rod decided it was time for a change, the entire team at Farmers, and of course Anne and I, are saddened and devastated by his sudden death," he said.
Mr McDermott started with Farmers as merchandise manager after being headhunted from Big W in Australia, and rose quickly through the ranks to head of merchandise for 15 years, before promotions to managing director and CEO.
"He was a top retailer, not just in terms of understanding stores, but really people and merchandise - probably the best I've worked with," Mr Norman said.
"You could just about a write a book about Rod, he was very talented, and he had an eye for detail that very few people possess . . . He deserves a great deal of credit for where Farmers is today.
"He really took it from almost a flat-looking business, and turned it into something that we're all very proud of," he said.
A tearful Liz Mitchell, one of the country's leading couture and ready-to-wear designers, said she was shocked and saddened to learn of Mr McDermott's death.
"It's such a tragic and terrible catastrophic thing to have happened. I feel so very sad."
Ms Mitchell said earlier in her career she and Mr McDermott worked closely together for 6-7 years launching and marketing her womenswear label in Farmers stores.
"Rod was instrumental in giving me this exciting opportunity, and he was very much part of how that came to change my life and how my business developed," she said.
"Rod was very much a straight-shooter but he was also a very astute and talented retailer, and I loved working with him . . . I feel so sad. It's a terrible loss."
A memorial service will be held for Mr McDermott at St George's Anglican Church, Ranfurly St, Epsom in Auckland, which starts at 2pm on April 5.
