There can be few more screeching handbrake career turns than going from the glamour of working on a fashion shoot in Sydney to picking vegetables in a windswept field in Essex.

Robyn Philip is part of a new 'land army' of key workers: essential to keeping our food supply chain going as it faces its biggest test since World War Two. I meet her as she comes back to her caravan, after a morning picking asparagus.

"I think I’d like to look back on this time thinking I’d done something for the community rather than sit at home waiting for jobs to come back", she says.

Farmers are desperate for help. Without their usual influx of migrant workers from the EU, thousands of tonnes of food risk going to waste in fields up and down the country, just as the summer crops come into season.

Every year our farming industry needs 90,000 seasonal workers. Like Robyn, many have put themselves forward - but in no way near the numbers needed.

Others are finding the application process hard to navigate.

Robyn Philip has swapped her styling job to work on a farm. Credit: ITV Tonight

Mark Thorogood, whose family have run the Essex farm for three generations, says it’s a perilous time for the food supply chain. "If we can't get the labour – it doesn’t get picked. That’s the crux of it", he said.

This week on ITV's Tonight programme, we've looked at our food supply chain from every angle - we've spoken to supermarkets, charities, truck drivers, manufacturers - just to see how they're coping during the coronavirus pandemic. We've also spoken to those for whom getting basic provisions has been almost impossible - and their stories are heartbreaking.

  • Farmer Mark Thorogood says it’s a perilous time for the UK's food supply chain:

It feels an age since those shocking scenes of panic buying - and the even more shocking sight of a nurse weeping because she couldn't buy food - but make no mistake: even though on the surface, things seem to have improved, this is a supply chain running white hot, stretched to its very limits.

For some, its bonanza time: supermarket sales are up an eye-watering £2 billion.

But with hotels, restaurants and cafes closed, parts of the food chain are struggling massively to adapt. While some people find it hard to get a bottle of milk, some dairy farmers are pouring thousands of litres of milk down the drain because the coffee shops they supplied are closed.

Charities aren't getting the usual leftover food supplies from supermarkets they depend on to donate to families in need.

The charity The Food Foundation claims more than one and a half million Britons are going without food for at least a day because of the pandemic and three million have experienced hunger since the lockdown.

Charities aren't getting the leftover food supplies from supermarkets they depend on to donate to families in need. Credit: ITV Tonight

On top of all that - the reality that nearly 50% of our food comes from abroad. With the numbers of ships crossing the Channel reduced and port workers hit by the virus, this is now under threat too.

So could this crisis see a permanent change in how we feed our nation?

The country's leading voice on food security, Professor Tim Lang gave us a grave warning: "The entire world food system is being disrupted. More disruptions are coming. Plantings not happening, food being wasted.

"Britain only produces about 50% of its food - the country that can only half feed itself has got to wake up".

  • Julie Etchingham presents Supermarkets and Supply Chains: Keeping Britain Fed - Tonight, broadcast on Thursday 23 April at 7.30pm on ITV