Asparagus is a serious business in Germany. The crowning of this year's "Asparagus Queen" last week opened a season when the entire country goes crazy for a vegetable believed to have cleansing and healing properties.

For the millions of Germans who anxiously await the asparagus harvest, this year's season could be an allegory for another issue that prompts equal anxiety: the eastward enlargement of the European Union, the primary objective of the Nice Treaty.

While Germans gorge themselves on asparagus each May, no amount of financial inducement from the German government can get unemployed Germans into the fields to harvest the vegetable themselves.

"Harvesting asparagus is a physically tough job. We have strong young men in Germany but they're not interested," said Mr Manfred Schmidt, head of the Asparagus Society in the town of Beelitz, south of Berlin, in the state of Brandenburg.

Instead, Germans leave the work to some 250,000 workers, mostly from nearby Poland and the Czech Republic, who arrive each May to pick fruit and vegetables in what the federal employment office calls "Europe's biggest annual legal migration".

Even highly qualified teachers and doctors in Poland have been known to take menial jobs picking fruit and vegetables in Germany. "For them, the incentive is that for a few months' work they can take home as much as they would earn at home in a year," said Mr Hugo Simianer, an asparagus farmer near the Brandenburg town of Busendorf.

Germany has the most to gain from EU enlargement, namely unprecedented access to a market to its east with 40 million consumers, but the government has its work cut out convincing Germans of that.

According to Deutsche Bank Research, German approval for EU enlargement has dropped from 38 per cent in 1999 to 34 per cent today, with barely 20 per cent of Germans convinced that enlargement is important for their interests.

For those in Germany's eastern states, where unemployment is running as high as 20 per cent, enlargement simply means a flood of cheap labour from the east.

The International Labour Organisation points out that nowhere is there such a discrepancy in income between neighbours as between Germany and Poland, where average wages are 11 times less.

On his tour of eastern German states bordering the Polish and Czech borders this summer, the German Chancellor, Mr Gerhard Schroder, will try to soothe fears of eastward enlargement.

No doubt he will restate his commitment to a seven-year transition period before workers from countries such as Poland and the Czech Republic can work freely within the EU.

Germany's federal employment office says that, even if labour restrictions were lifted immediately, the EU could count on about 200,000 to 250,000 people migrating from central and eastern Europe in the first five years after joining the EU.

The number of central and European workers entering Germany's labour market would be no higher than 90,000 in the first year, according to the report, a negligible percentage of Germany's 38 million workforce.

Few Germans have paid heed to the statistics, though, and by the time accession talks heat up next summer, Germany's general election campaign will be in full swing.

Mr Schroder is anxious not to let the opposition take advantage of vague fears of low-wage workers taking jobs. "Right now, nothing drives politics better than fear," said an official at the congress of Ver.di, Germany's new super union. "Most of the point of this whole debate is psychological," he said.

A more pressing concern for the German government is the cost of enlargement. The German economy is only just back on track after a disastrous decade caused by underestimating the financial black hole of German reunification.

The prospect of another decade of payouts, this time to Germany's eastern neighbours, does not appeal to Germany's prudent finance minister, Mr Hans Eichel. He has sounded more than a little worried about enlargement recently, insisting that accession states must reach economic reform targets to become members of the EU.

"The economic criteria must be fulfilled, not because we want to anger anyone, but because otherwise the people will experience a shock," he said earlier this month. "If we agree to the wrong package on this question, this will not be a contribution to European integration," he said.

In a recent report, Germany's Dresdner Bank said that, if EU subsidies were kept at current levels, the cost of enlargement could be as high as €44 billion in 2005 alone, though the EU budgets only €14 billion for the same year.

As the EU's largest net contributor, Germany is worried about who would foot the bill for any financial shortfalls caused by enlargement.

Asparagus farmer Mr Schmidt belongs to the one-fifth of Germans who support the enlargement of the EU.