Peter Reeves has concerns about Brexit.

The soft-fruit farmer grows about 2% of all the blackcurrants that go into Ribena as well as grapes for Chapel Down Wines on his land in the Weald.

He relies on migrant labour from Eastern Europe to pick and prune his fruit each year.

He was alarmed to hear Prime Minister Theresa May rehash the “tens of thousands” immigration target in the Conservative manifesto, first set by predecessor David Cameron in 2010.

“Without migrant labour we wouldn’t have a business or an industry,” he said at a networking lunch at the Kent Vision Live business exhibition on May 10.

“Is Theresa May purely electioneering to get more Ukippers on board or is it serious? What will be the financial impact on the UK?”

Mr Reeves uses a licensed gang master to bring over mainly Romanian workers, who “come for around 12 weeks, go home for several and then back again as needed”.

Out of 1,200 the gang master has brought over, only two have stayed in the UK.

He said: “The Prime Minister saying the future government should get immigration down to the tens of thousands is very worrying.

“She never achieved it as Home Secretary and the only way she will achieve it now is by tanking the economy – something none of us want.”

Mr Reeves’ industry is not the only one concerned about immigration.

Professor Richard Whitman is head of the school of politics and international relations at the University of Kent.

“UK higher education can’t work without international students. We would be stuffed, frankly..." - Prof Richard Whitman, University of Kent

“We acutely feel the issue of immigration in education because 20% of students are international,” he said.

“It’s hit us hard.

“UK higher education can’t work without international students. We would be stuffed, frankly.

“We are a successful export sector and it doesn’t make any sense to be constraining these numbers. We need a sound immigration policy.”

The concern has also stretched to the construction sector.

Peter Stringer, chief executive of Maidstone-based housing association Golding Homes, said: “The construction world generally employs a fair amount of migrant labour.

“When the crash hit in 1989, the chief executive of Barratts said then that we lost 600,000 skilled construction workers from the sector. We have concerns about that.”

James Sproule, chief economist at the Institute of Directors, was a guest speaker at the Kent Vision Live show.

“I have spoken to ministers on the issue of immigration and the word they keep using is ‘control’,” he said.

“That is a lovely word which is very flexible. There is one minister who is adamant there needs to be a number and she occupies Number 10.

“There is a good deal of debate within the government over what that means.”

However, there is some optimism that a good compromise can be found on EU migrants.

Richard Balfour-Lynn, owner and producer at Hush Heath Winery near Staplehurst, relies on European pickers during harvest season.

He said: “I think the government will undoubtedly allow people to come over for three month stays like they do now. I can’t see that changing.

“Brexit is a great opportunity. You can look at the downsides but none of us know how it is going to play out.

“For the next few years that does create uncertainty.

“But from our perspective, we are going to have more people staying in Britain, and the weakening pound means we are exporting more effectively to the States, Japan and Hong Kong.

“I’m very positive. British brands have a great opportunity to continue to grow.”