Coxheath, England(CNN) The workers traveled purposefully down the polytunnels, hands moving swiftly as they plucked plump raspberries and blackberries from the canes. Any delay means less pay.
It's hard work. But the picking teams at Clock House Farm, in southeast England, have traveled more than 1,000 miles to be there, leaving family and friends behind.
Why do they come? "For money," said Romanian picker Alin Florea succinctly. "It's double or more what I would get at home."
He's worked at Clock House Farm for the past eight summers. But, the 29-year-old said, it's not easy saying goodbye to his family, including a 2-year-old daughter, for four months at a time and this year could be his last. Back home, he works as a driver or window fitter.
Farm owner Robert Pascall said he's managed to get enough pickers this year, with 550 signed up, most of them Romanian. "It's been a bit touch and go and quite expensive recruitment -- and obviously we've seen quite significant wage inflation because it just has been difficult to get people," he said.
Over 30 years Pascall has seen his business, located an hour southeast of London, expand from 200 to 1,000 acres as he's taken over struggling farms nearby.
With the advantage of scale, he can compete. But a tiny operating profit margin leaves his business vulnerable to increasing labor costs.
Across the European Union, seasonal agricultural workers are at a premium. Most come from the eastern European nations that have most recently entered the bloc -- particularly Romania and Bulgaria -- but as economic conditions in their home countries improve, the number willing to travel elsewhere in Europe for short-term manual work is dwindling.
Germany's agricultural sector relies heavily on seasonal workers, with 180,000 Romanians and 100,000 Poles employed in 2016. In the face of falling numbers, some farmers and politicians called in German media reports this year for Ukrainians also to be allowed in.
Spain already employs thousands of seasonal workers from Morocco to harvest its crops, particularly strawberries. A spokesman for Spain's employment ministry confirmed that married women with children are preferred because they are considered most likely to return home when their contracts end.
And in Portugal, thousands of seasonal agricultural workers are recruited from as far afield as Asia and Africa, according to the Confederation of Portuguese Farmers, as well as from non-EU European nations such as Ukraine and Moldova.
Meanwhile, Poland -- itself a source of migrant labor for some wealthier European nations -- now brings in workers from non-EU neighbor Ukraine to meet its own labor needs, according to data from the Kiev-based think tank Centre for Economic Strategy.
Britain, which according to the National Farmers' Union employs 60,000 seasonal workers in the horticulture sector each year, does not currently allow in seasonal agricultural workers from outside the EU. And it is feeling the squeeze.
There's a 10% shortfall in such workers so far in 2018, according to NFU figures released last month, following a 12.5% shortfall in workers recruited by labor providers for 2017.
After many months of lobbying by farmers' groups, the UK government earlier this month announced a two-year pilot program to bring up to 2,500 non-EU migrant workers a year to work on British farms for up to six months. Agricultural bodies widely welcomed the news -- but pointed out it was only a small step toward what is needed.
"Our farms are reporting staff shortages of 10%-20% already, and to have any effect in terms of supporting our successful industry ... around 10,000 are needed now -- not 2,500," said Nick Marston, chairman of British Summer Fruits, an industry body for soft fruit growers.
"At least the powers that be are at last taking a bit of notice," said Pascall. "Basically, the industry, or the government, has a choice: either exporting the industry or importing the labor. There's no alternative."
There's a lot at stake. Soft fruit production in the UK has grown by 130% in the past 20 years, according to government figures. If workers can't be found to pick Britain's strawberries, raspberries, blackberries and blueberries, farmers must reduce what they plant or risk seeing precious crops rot.
While it's far from the only factor at play, Brexit has not helped. The fall in the value of the pound since Britain voted to leave the EU means wages offered by British farmers are less tempting than those elsewhere in Europe.
There's also wide uncertainty over the future status of EU seasonal workers after Britain exits the bloc next March.
As fraught negotiations with Brussels continue, the prospect of a potential no-deal Brexit has prompted dire warnings of food shortages, among other issues, and a renewed focus on self-sufficiency.
The UK's peak picking season runs from May to November, with the earlier months dominated by soft fruit and the later ones by so-called top fruit, such as apples and pears.
September, when both soft and top fruit need picking but many workers are ready to return home, is a particular pinch point.
According to the NFU's labor providers' survey, about half the seasonal agricultural workforce is resident in the UK, while the remainder travel there for work and then go home. Two-thirds come from Romania and Bulgaria, which became EU members in 2007, with just over a fifth from eight eastern European nations that joined the EU in 2004, Poland among them.
Only 1% of the sector's seasonal workers are native to the UK, where unemployment currently stands at a 40-year low.
Ali Capper, who chairs the NFU horticulture board and runs a West Midlands farm producing apples and hops, has worked hard to recruit British workers this year, including placing ads in local newspapers and colleges.
As a result, she has managed to sign up six UK workers. "It's an unprecedented number but also an effort, all of which adds to our cost and workload," she told CNN.
Capper fears the impact of a no-deal Brexit next March. "It's potentially catastrophic. The sector requires 60,000 seasonal workers for about 80,000 seasonal roles," she said.
She wants a program brought in to recruit non-EU workers that would help Britain compete with other European nations.
Britain operated such a program from the end of World War II until late 2013. It was phased out when restrictions on the free movement of Bulgarians and Romanians were lifted.
By 2016, Capper says, farmers were starting to see significant labor shortages -- a situation that has worsened. Last year, a lack of pickers cost her own business, Stocks Farm, about £30,000 when good apples had to be sent for juice because they were harvested too late, she said.
Amid stiff competition to attract pickers, farms are now paying seasonal workers a higher wage, upgrading their accommodation and offering end-of-season bonuses.
"It's not unusual for (seasonal workers) to be paid between £12 and £15 an hour," said Capper. The current national minimum wage in Britain for workers aged 25 and over is £7.83, with lower rates paid to younger workers.
Meanwhile, the profile of the pickers has changed, Capper said. Whereas before they were often young, fit students who wanted to improve their English, recruits are now generally older, less well educated and less productive. Labor agencies increasingly have to travel to rural areas of the EU to find workers, she added, hence the focus on Romania and Bulgaria.
A key factor in the changing profile of recruits is the strengthening of Romania and Bulgaria's own economies. The former, with a population close to 20 million, enjoyed 6.9% growth in gross domestic product last year, according to European Commission forecasts, while GDP in Bulgaria, with about 7 million people, grew by 3.6%.
As economic conditions improve, workers' options are changing. "People we've had for some years are being offered almost the same back there as we can offer here," said Pascall. "And there is where they would rather be."
Meanwhile, farmers in Britain increasingly have to contend with pickers who don't turn up as promised, are less motivated to work or leave sooner than expected, Capper said. Two of the 20 workers she recruited from Poland this year didn't show up.
"The big hurdle is, we are talking about seasonal roles which in order to have year-round work means people have to move around the country, which just doesn't suit the aspirations of any 'First World' country," said Capper.
"Other countries in the EU are recruiting from outside because there aren't enough workers in the EU."
Amid the uncertainties over future labor supply and Brexit, some British soft fruit farmers are developing interests in other EU countries and further afield, said Capper, including China, South Africa, New Zealand and Australia. Others are delaying investment decisions at home, she said. "We just don't know if we are going to have access to the people we need to pick the crop."
Stocks Farm has been in her husband's family since 1962. "Times now are the most challenging we've seen," said Capper. "I've never known it like this."
Meanwhile, Pascall is determined to do all he can to keep his seasonal workers coming back -- he currently has a 65% return rate. The farm's website is translated into both Romanian and Bulgarian. He plans to send newsletters during the winter to foster ties with this season's pickers.
The farm's permanent staff include Romanian nationals who first came for a summer but stayed on and rose through the ranks. Having been resident in Britain for several years, they shouldn't be affected by Brexit.
Picking team leader Alexandru Gitlan, 27, from the southeastern Romanian city of Calarasi, is one of those. He doesn't believe the situation in Romania has improved enough for workers to stop coming.
Anna Maria Petcu, 26, also from Calarasi, recently finished a college course in management and is working her third season at the farm. "I want to find something in Romania but I don't know what I will find," she said. She fears Brexit will make it more difficult for workers like her to come to Britain.
Bogdan Dumitra, 33, from the southern Romanian city of Craiova, is in his eighth season at Clock House Farm and heads another of the picking teams. He and his fiancée, also a picker, will marry in two months when they return to Romania.
Dumitra keeps coming back for the money, he said. At home, he works in a hospital but earns less. "It is hard moving back and forward," he said.
Things have changed since the Brexit vote, Dumitra added. "It is a bit different but it's still OK for us. It's just the political atmosphere."
So long as Pascall can keep his pickers coming, he sees opportunities in Brexit. If the value of the pound falls, homegrown produce becomes more appealing. The government may step in to soften any blow to British growers, he said, and new markets could open up.
"I think we've just got to get on with it and make it successful," he said.