“Better than you might think.” As advertising gambits go, it’s not one to set the pulse racing exactly. But that, essentially, is the message behind Lidl’s recent wine PR splurge.

It was a message that was hard to avoid last autumn when the German supermarket splashed the cash to advertise its range, including 48 new, so-called “fine wines” – which, at a cost of £12m, was its biggest UK product launch.

Rather like the excruciating scene in the recent BBC documentary about Tatler where the magazine’s fashion editor titters her way around the Notting Hill branch of Poundland, the idea seems to be: hey, you, the middle class and, yes, even you poshos, Lidl is safe for you! Yes really! We know you love our stollen and gravadlax. But we have £12 Champagne and Château Sociando Mallet at £25.99 a pop too!

It seems to be working. Certainly, the sales figures for both Lidl and its even more successful German budget co-conspirator Aldi have had executives at the big four British supermarkets fretting. According to a recent report by market researchers Kantar Worldpanel, Aldi’s share of the UK grocery market grew by a third last year to 4.8%, and Lidl by around a fifth to 3.6%. Of the big four, only Asda had avoided a drop in market share.

Both Aldi and Lidl have aggressive expansion plans, with stores in the more affluent parts of London and the south east very much in their sights. And wine – as it is at the big four supermarkets – is seen as a key way of getting the middle classes through the door.

That campaign received a high-profile boost late last year, when the experts behind a new app, wotwine?, declared Lidl the best supermarket to buy wine, with Aldi in second place. The findings, based on blind tastings of more than 4,000 supermarket wines, suggested that 65% of Lidl’s wines (and 64% of Aldi’s) were good value for money, against 35% (36% for Aldi) that were poor value. This compared to 45% and 55% for Tesco, and a damning 26/74 ratio for Marks & Spencer.

While it’s possible to take issue with the faux-scientific precision of these ratios (which were, after all, the product of a series of subjective tastings and suggest that “value” in wine is a fixed, objective idea when it really isn’t), the findings weren’t all that surprising to me (although I might have put Aldi just ahead of Lidl). All supermarkets buy on price to an extent. But Aldi and Lidl, it seems to me, do it to the expense of anything else. Other supermarkets will have a set of wines that they feel they have to list to be credible, but if the discounters can’t find a wine style, grape variety or region at a suitably arresting price, they simply won’t list it.

That means their ranges are significantly smaller, even a little eccentric compared to their rivals, and there’s a distinct feeling of you’ll get what you’re given when you shop there. From what I’ve tasted of both retailers, with a handful of exceptions, the relentless focus on price also tends towards the consistently quite good rather than the great. There may, as wotwine? says, be some bad value wines at M&S. But for my money the wines in its “good” 26% will be so much more interesting than anything at either Lidl or Aldi. What’s more, the discounters’ “bad” “35%” will have more than its fair share of stinkers (I’m looking at you Aldi Cantata Barolo) – wines that are, quite frankly, even worse than you might think.

Six best Lidl and Aldi wines

Cimarosa Pedro Jimenez, Chile 2013

(Lidl, £3.99)

A grape best known for making treacly sherry in Spain and as the base for the South American pisco grape spirit, Pedro Jimenez (or Ximenez) is increasingly turning up in dry white wines from Chile, here providing a crisp, clean, citrussy no-frills seafood match.

Lidl Chianti, Italy 2012

(Lidl, £4.39)

The wine that inspired the approving tweet from a punter that went on to feature in a Lidl billboard ad, this does a very good job for the money: with its tomato-like acidity and cherry and plum fruit, it’s a good match for mid week spag’ boll’.

Lidl Barolo, Piedmont, Italy 2009/2010

(Lidl, £11.99)

This may not quite have the tar-and-roses mix of power and ethereal fragrance of top barolo, but then neither does it have the price tag, and with its mix of forest floor and fruit and sand-paper tannin, it’s a fine budget introduction to the nebbiolo grape.

The Exquisite Collection Limoux Chardonnay, Languedoc, France 2013

(Aldi, £6.99)

Star buy: Limoux’s elevated position gives it a slightly cooler climate than the rest of the Languedoc that makes it ideally suited to Burgundy-style chardonnays such as this, which, with its rich creamy-savoury flavours, and crisp-apple freshness, is stunning value.

The Exquisite Collection New Zealand Pinot Noir 2013

(Aldi, £6.99)

This is a crazy price for Kiwi pinot noir, which only very rarely comes in at under £10, and is usually undrinkably stewed when it does. Not hugely complex, but what it lacks in silkiness it makes up for in redcurrant freshness and bright cherry-berry fruit.

The Exquisite Collection Gavi, Piedmont, Italy 2013

(Aldi, £5.49)

Another supermarket staple these days, but again rarely at this sort of price-value ratio, this super-tangy but fluent dry white is full of lemon zest and pith for herby, garlicky chicken or white fish served with salsa verde or aioli.