Mr Gault's wife and co-founder of the centre, Dorothy will assume the role with immediate effect, as Klondyke explains it is "very much business as usual in respect of the group and its ongoing development".
Klondyke chief executive Bob Hewitt commented: "We will continue to build on the success of the business to date. During the coming years we will be undertaking a number of planned redevelopments and refurbishments within the existing estate with the aim of further improving sales and profitability.
"Bob Gault will never be forgotten for his drive, enthusiasm and passion both for the Klondyke business and the Garden Centre industry. We owe it to him to continue to drive the business forward."
The family-run firm was established in the 1980s when Bob and Dorothy Gault bought a struggling garden centre site in Kirkintilloch from which to run their camping supplies company.
Klondyke now operates 25 garden centres throughout Scotland, Northern England and Wales. Its six Scottish centres trade under the Klondyke name, while the 19 garden centres in England and Wales operate under the name of Strikes Garden Centres; following a merger with another family run garden centre group, William Strike Ltd in 1996.