Brykley, Garden Centres of Cheshire, Holland Arms on Anglesey, Brookside Garden Centre in Cheshire and Merseyside-based Lady Green were recent buys. In 1996, Klondyke bought seven William Strike garden centres, which doubled its size and extended the group into the north of England.
Recognised as a true entrepreneur, Gault saw the business grow to reach turnover of almost £50m and staff numbers around 1,000.
A Klondyke statement read: "Bob's passion and enthusiasm for the garden centre industry was well known and he will be sadly missed by all in the industry who knew him, his many long-serving members of staff and the board of directors of the company. Our thoughts are with (his wife) Dorothy and her family at this most difficult time."
Klondyke chief executive Bob Hewitt added: "The business was owned by Bob and is still owned by his wife Dorothy, which means it will carry on as always. Bob was a very enthusiastic spokesman for the industry and I will miss him.
"He will be missed by the whole industry. I've had lots of phone calls and messages from people in the industry. Many things he said about the industry came into fruition and were true. He was very passionate about Klondyke and the industry."