Clancy Group joint chairman Dermot Clancy was crushed to death last September when the mower he was using to cut his grass tipped over on top of him, an inquest heard.
He was found underneath his Kubota tractor-mower in a hollow in a field he owned, next to his large family home in Penn, Buckinghamshire.
Coroner Crispin Butler said Clancy, 67, died as a result of misadventure.
The senior coroner for Buckinghamshire said: “The tractor has fallen on Clancy when he was doing something he liked to do on his land.
“It is a very, very sad accident. It was an ordinary activity that sadly went tragically wrong.”
The inquest in Beaconsfield heard the father-of-five was found by his wife and neighbours Giles and Sue Robinson.
Clancy was pronounced dead at the scene, caused by traumatic asphyxia.
Detective Constable Lucy Berry of Thames Valley Police, told the inquest: “I was made aware he did enjoy mowing the lawn. The house was really far back from the land [where he was found].
“It was very, very steep. You had to go to the edge to see down into the dip.”
The inquest heard that the tractor-mower was examined, but no defects were found.