Christopher Self, chairman of Whitehall Garden Centre in Lacock, Wiltshire, has died at the age of 76 following a heart attack.
Mr Self's death comes less than a year after that of his mother, Phyllis Self. Both had worked at the family-run business for some 40 years.
The garden centre will now continue to be run by Christopher's son Peter, who is managing director, and his wife Claire, who hope that their two daughters will also be joining the business.
Peter says he intends to set up a trust in his father's memory, which will help to support local clubs and other organisations.
Phyllis Self was 105 when she died last year. She had retired only two years earlier and was dubbed "the oldest boss in Britain".