It's always five o'clock somewhere, goes the sot's adage. This sound principle may also be applied to the seasonality of fruit and vegetables. These days, the year-round availability of everything from Peruvian asparagus to Dutch tomatoes is pretty much ubiquitous in UK supermarkets. Such disregard for British growing seasons has become something of a cause célèbre for foodie types, and a new survey by BBC Good Food Magazine has found our knowledge of the seasons to be pitiful.
Of the 2,000 people polled, only 5% could say when blackberries were plump and juicy. And 4% guessed accurately at when plums were at their best. One in 10 could pinpoint the season for gooseberries. All of this is despite 86% professing to believe in the importance of seasonality, and 78% claiming to shop seasonally.
In the great scheme of our foodish shortcomings - the obesity, the steady rise of ready meals, our unwillingness to cook - does it really matter if people don't know when a broad bean is in season? Jack Adair Bevan runs the Ethicurean restaurant in Bristol, which, as far as possible, cooks with the seasons using produce grown in its walled garden. Despite this laudable approach, he's not about to lambast those who aren't so attuned to nature's flux. "We're pretty spoilt in the sense that having a garden means we have it all here - our eye is on the seasons constantly. But I can see it would be hard for someone without a garden. If all they have to go on is what's in the shops, well, you can get pretty much anything all year round."
Thane Prince, author of Perfect Preserves and a judge on the BBC's Big Allotment Challenge, agrees. "I think it's quite tricky, because there's always something in season somewhere," she says. "It's a matter of trying to make sense of the seasons these days, and there is a natural body clock to food that makes seasonal food taste better."
To be sure, quality of flavour is and should be high on the list of why it might be worth being in touch with the seasons. A pale January tomato is a foul thing. A strawberry at the Christmas table would be an aberration. Or would it? "I think they seem wrong because they don't taste good," says Prince. "If you could find amazing tasting strawberries in December then, for many, that would be far preferable to Christmas pudding."
Arguments in favour of seasonal eating go beyond flavour, however. The nebulous spectre of localism, inevitably, materialises. If you were to argue that, in a blind tasting, most of us wouldn't be able to tell the difference between British and Peruvian asparagus, you would, in all likelihood, be met with a volley of argument concerning air miles and freight and footprints. This is largely bunk. Unless you live in an asparagus-producing part of the country - the Vale of Evesham, say - then the ecological impact of Peruvian versus British asparagus is vanishingly small. If you drive to the supermarket it is nixed altogether, if not tipped in favour of Paddington Bear's homeland.
There are floatier arguments. In an interview in 2010, Guy Watson, founder of the Riverford Organic vegetable box scheme, says "I am an advocate of local food, partly on environmental grounds but mainly because I think it's important that people feel a connection with where their food comes from." We can, in this instance, conflate local with seasonal, but it doesn't get us much closer to a strong argument for shopping seasonally. Other seasonal cheerleaders use words such as "harmony". It's a nice idea, but it's as wishy-washy as any winter strawberry.
More concrete, if not entirely watertight, are economic arguments. The law of supply and demand dictates that June's glut of strawberries makes for a cheaper product than you'll find out of season. Anyone who has ever eaten a Jersey Royal, on the other hand, will know that seasonal doesn't necessarily mean frugal.
Perhaps the most compelling argument of all is that of simply supporting British producers. Unless you're after blood oranges or pineapples, by shopping seasonally you should, by and large, find yourself buying British. Irrespective of food miles or flavour, it is thoroughly depressing to find supermarkets selling Peruvian asparagus in mid-May. In 2012, only 23% of the fruit and vegetables we bought were home grown. We're only a small country, and far from self-sufficient, but we can do better than that.
Ultimately, however, our understanding of food seasons, while clearly leaving room for improvement, is less of a concern than countless other defects in our relationship with food. There was a time when the "hungry gap", was a cause for genuine alarm, the unyielding fields making for spartan dinner tables. I can't help wondering if our forebears wouldn't be tickled by our sniffiness at eating green beans in March.
Arguments in favour of seasonal eating go beyond flavour. The nebulous spectre of localism inevitably materialises. Photograph: Alamy