The 10ft square hole, signposted Heseltine's Bore, was dug by nearly 50 people, some armed with shovels and pickaxes, in the garden at Thenford Hall, Northamptonshire.
The group, including environmentalists, ex-miners and members of the pressure group, No Opencast Mining, left Mr Heseltine's land around 11am.
Although they assured police officers that the turf would be replaced before they left, it was not. It is not known whether Mr Heseltine witnessed the protest, but it is understood he was at the house for lunch.
Northamptonshire police said it was a "peaceful protest" with no arrests and there were no plans to prosecute anyone.
The protest organiser, Steve Parry, said the group wanted to dig a borehole on Mr Heseltine's land after cuts in the deep mining of coal had led to a growth in open-cast mining which ruined the environment.
A spokeswoman for the Deputy Prime Minister said: "He has absolutely no comment to make."
One miners' supporter, Terry Hutt, 62, from Essex, said: "We just wanted to highlight some of the things Mr Heseltine has done. Lots of people don't like it."
Mr Parry said: "We want to show Michael Heseltine in detail what happens to local community public spaces when per- mission is granted for an open- cast mine."
The demonstration was co-ordinated by the London-based MSG Associates (Miners Support Group), which said in a statement that the protesters had turned Mr Heseltine's Northamptonshire retreat "into an open-cast mining site".
Campaigners have lodged a planning application to develop an open-cast mine on the site, and claim the borehole is needed to test water levels before further work.
Mr Parry said he believed Mr Heseltine had written to North-amptonshire County Council to "fiercely oppose" the plans.Reuse content