Cheap veg - the surprising stories behind humble British vegetables. Sheila Dillon enlists three experts to uncover the hidden side of our veggies.

Ethno-botanist James Wong argues that rhubarb is the only uniquely British indigenous vegetable. Agricultural expert Dr Oliver Moore discovers the work that a seed bank in Ireland is doing to increase variety in our potatoes. And food writer Andrew Webb unearths new uses for onions.

Presented by Sheila Dillon and produced by Emma Weatherill.