By Dominic Casciani
BBC News Online community affairs reporter
If there is anywhere in the UK where immigration is playing a major part in the economy, then it's in agriculture - and there are many businesses that say they can't survive without their foreign workers.
Cutting the crop: Workers from eastern Europe
There is a corner of an English field that is today forever foreign.
Immigration has risen up the political agenda in the wake of rows over asylum and accusations of wider mismanagement.
But many farmers increasingly stress how much they rely on migrant labour - even if the country remains undecided.
So today if you buy a celery from Tesco, Sainsbury or Marks and Spencer, there's a chance it may have been picked, chopped, washed and packed by Mariusz, Dorota and Darius - just three of the 1,600 eastern European workers who have spent this year at G's Marketing, a major Cambridgeshire-based enterprise with farms in the UK and Europe.
Although it has a turnover of some £135m, it's the kind of company consumers know little about, but which is essential to supermarket-dominated food production.
When the stores demand thousands of extra celery ahead of a barbecue bank holiday, companies like G's supply it within hours of an order.
It's a hugely competitive business and it relies on constant innovations in picking, packing and delivery.
From field to lorry pallet can take just minutes if the right team is cutting the crop, saving time and costs.
All of this requires a reliable and motivated workforce: long gone are the days when farmers relied on seasonal labour drawn from local people and travelling folk.
Searching for workers
Sharon Gudgeon runs G's international recruitment programme and said they first looked abroad in the early 1990s when part-time local workers simply disappeared.
"Someone in Britain is not going to give up a full-time job for a seasonal job," she says.
"And in terms of part-time, people prefer to have four-to-five hours a week every week at a supermarket, rather than work just for one season."
So when G's started looking for solutions, it ended up looking abroad and becoming a key player in the national seasonal agricultural worker scheme (Saws).
Saws aims to provide a supply of seasonal labour - and migrant workers with a route into the labour market without a right to stay permanently.
G's is among the group of businesses which pioneered Saws and remains a strong supporter of both it and the Home Office's work-permit system.
Supporters of migrant-worker schemes say it guarantees dependable labour for their businesses - and ultimately good prices for the customer at the checkout.
Most importantly, it seeks to avoid the uncertainty of undocumented workforces controlled by independent "gangmasters", currently the source of continuing concern after a string of high-profile illegal immigration rackets were uncovered.
G's' own recruitment starts six months before crop-picking.
The system has changed considerably this year as some of the countries used for recruitment are now members of the European Union, meaning workers are essentially free to come and work for G's without needing government permission.
Post from home: Office full of parcels
For non-EU countries, the company still needs to negotiate with the Home Office over its needs and then contact partner universities, the sources of its workforce. Source countries currently include Poland, Lithuania, Bulgaria, Ukraine and Moldova.
Recruitment is finalised when a team from Cambridgeshire travels east and makes a presentation to the students before they sign on the dotted line. Paperwork is completed and the staff travel to UK for the season.
"The students know what it is all about. We are very clear that it is a seasonal agricultural job," says Sharon Gudgeon.
"They are under no illusions. We don't give any false promises and we try to emphasise that while it's hard work, it will be a positive experience."
And the students appear to share that view. The atmosphere on the farm is as close as it can be to laid back in a multi-million-pound industry.
Students who spoke to the BBC had no complaints - in fact most had nothing but good words for the experience. Very few quit (seven this year) and, says Sharon Gudgeon, immigration breaches are virtually unheard of.
Keir Petherick: "Workers essential to business"
Part of the reason may be the atmosphere on site created by the purpose-built hostel which houses the majority of the workers.
Parcels from across eastern Europe stack up at the reception, addressed to Balintelis, Gajkowski, Jaszewski and others.
Amid the multi-lingual banter in the office, there are timetables for buses home to Poland and elsewhere while information is posted in a variety of languages.
The workers sleep in bunk dorms but also have entertainment facilities, free English lessons twice a week and barbecues and a sports pitch for summer nights. On days off, there are coaches to tourist attractions such as Oxford or Alton Towers.
So while the work is hard, most seem to see it as a bit of an adventure, a taste of something foreign without the risks of jumping on a bus to Britain with no job to go to.
And for farm director Keir Petherick, that's just the way he wants it. Watching over the day's production in the fields, he says G's would be largely "paralysed" without the success of its migrant worker programme.
"We had great concerns when we first did this that people would come over here, start working, get a bit wet and they would then up and leave to try and find work in London.
SEASONAL AGRICULTURAL WORKERS SCHEME
Aims to tackle labour shortfalls
Expanded in 2002
Companies manage recruitment
Applies to non-EU recruitment
2004 quota: 25,000 permits
"It's not been like that at all, partly because we've spent a lot of time trying to make sure people like the place, and like us."
Recruiting may be a logistical challenge not necessarily part of everyday farming - but it creates an efficient business and customer confidence, he says.
"If you have the means to bring in and control who you recruit, then it's a must for any major business like us.
"The gangmaster system involves a constant turnover of staff, the farmer has no idea what happens to the money he hands over.
"The workers may not even be legal because he can't check documentation. It can be a total nightmare. We don't have those problems here.
"When we put up the hostel, it cost something like £250,000 which is a lot of money at the end of the day. But it was a shrewd move because it gave us a secure workforce at a time when others did not have anything like this.
"Most importantly, our customers know we have a workforce they can also trust."