Spain - the land of leathery, over-oaked, vomit-scented reds and dark yellow, old cologne-scented, oxidised whites - has finally come of age. No other European wine-producing country has changed so dramatically, and for the better, in the past 20 years. When I was a baby wine writer, back in the late Seventies, it was easy to spot Spanish wines as they were always the foulest bottles in any blind line-up, with Don Cortez's 1.5-litre medium dry white the bottom of the barrel. Not any more.

Spain's first step forward from the Dark Ages was joining what is now the EU in 1986. That attracted new investment and brought with it huge subsidies for exports and vineyard restructuring. By the early 1990s squeaky-clean new wine-making technology arrived and the Spanish obsession with oak started to slow down as wine-makers discovered the delights of barrel-ageing as seasoning rather than the main dish. One by one Spain's wine-making regions came up with rafts of exciting, fresh, fruit-filled whites and reds.

With almost three million acres under vine, Spain is easily the world's biggest vineyard owner but only the third-largest producer of wine, so it was a worry that the legalisation of drip irrigation in 1996 would result in wishy-washy whites and reds. So far I have not tasted any dilution in flavour, and with less than a quarter of the country's vineyards irrigated and yields still hovering around 30 hectolitres a hectare, roughly half what French vignerons crop, I doubt that I will.

Nowhere is Spain's shift from ancient to modern more obvious than in the choice of grape. For decades now airén - the country's humdrum, neutral white grape, previously used in brandy production - has been losing ground to finer varieties such as chardonnay and viura, sauvignon and verdejo. Ditto with reds, as the lesser, faintly spicy garnacha (grenache) has lost out to Spain's greatest red wine grape, the rich, plummy tempranillo, responsible for such treats as rioja and ribera del duero. Bobal and monastrell plantings are up, too.

Experience one of Spain's revolutionary whites in the glorious lively verdejo-sauvignon blend of top-spot Rueda's 2007 Los Pecadillos Envidia (Highbury Vintners, 020-7226 1347, £7.99). Good, cheap, fruity Spanish reds abound and Cariñena's garnacha-based 2007 Salduba (Waitrose, £4.99) has lots of delightful, bold, earthy spice. So, too, has the unusual, inky, violet-scented alicante bouschet grape-based 2007 Higueruela Tinto from Bodegas Tintoralba in Almansa (Halifax Wine, 01422 256333, £6.99). Even rioja is far less stringy than it was, with the top-dog 2006 Viña Herminia's Excelsus (Oddbins £10.49) all ripe, seductive fruit, and Ribera del Duero's 2005 Roble from Basconcillos full of magnificent burly, spiced plum (Vintage Roots, 0800 9804992, £9.99).

Best buys

2007 Cuvée de Richard, Vin de Pays de l'Aude, France Majestic, £3.79 until Monday. A carignan and grenache-based red whose joyous, juicy, dusky fruit makes it one of the best- value French reds in Britain.

2008 Esperanza Sauvignon Blanc, Mendoza, Argentina Majestic Wine, £5.32 or buy two for £3.99 each. Terrific, cheap, peach-scented Argentine white partner to the Esperanza red of a fortnight ago.

2008 Les Montgolfiers Sauvignon Blanc-Gros Manseng Reserve, Vin de Pays des Côtes de Gascogne, Thierry Boudinaud, France Tesco, down to £4.99 until April 14. Delicious, exotic, gooseberry and apricot-stashed new Gascon blend.

2007 Les Montgolfiers Shiraz Reserve, Vin de Pays d'Oc, Thierry Boudinaud, France Tesco, down to £4.99 until April 14. Impressive chocolate and berry-laden Languedoc shiraz named in honour of M Boudinaud's balloon-mad ancestors.

The keeper

2002 Château Croizet-Bages, Pauillac, Bordeaux, Sainsbury's, down to £19.99 until April 14. Easter early birds need to fly into Sainsbury's to scoop up this tasty fifth growth, a lively, gamey, smoky, tobacco and cedar-scented claret that is drinking deliciously now, especially with roast lamb, but will continue to mature for a few years yet. Drink now until 2011.

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