Portugal has undergone something of a wine revolution in the past couple of decades, updating its winemaking technologies, styles and attitudes. This archetypal Old World country has long been famous for little more than its fortified wines (Port and Madeira) and tart, light Vinho Verde. But it is now attracting a great deal of attention for its new wave of rich, ripe, table wines – particularly reds from the Douro Valley.
One might argue that Portugal's place in the wine world has centered more around its cork production than its wine, but this depends largely on which period of history one chooses. In the 18th century, when the supply of French wines to England was threatened by deteriorating international relations, Portugal's vineyards proved more than capable of filling the void. It wasn't until the 20th century, when international demand for Portuguese wines had dwindled to almost nothing, that Portugal rose to dominate world cork production. In the 21st century, the Portuguese cork industry is struggling (due to the ever-growing popularity of plastic corks and metal screwcaps), but the nation's wines are once again on the rise, led by dry reds from the Douro and Dao.
Portugal's many vine varieties and their countless regional synonyms are the bane of ampelographers. Some are endemic to Portugal (e.g. Touriga Nacional), while others are shared with neighboring Spain (e.g. Tinta Roriz/Tempranillo). An increasing number are the ever-popular 'international varieties of French origin (e.g. Cabernet Sauvignon and Chardonnay). Happily, the current success of Portuguese wines has not become dependent on the latter category - a fact which has played to its favor; by retaining their indigenous grapes, Portugal's winegrowers have maintained a certain uniqueness in their wines, which is a valuable asset in the world's increasingly demanding and competitive wine market.
Portugal's temperate, predominantly maritime climate has a great deal to offer ambitious vignerons. The country's portfolio of terroirs is not as broad as that of, say, France or Italy, but there is significant variation nonetheless between its mountains, river valleys, sandy littoral plains and limestone-rich coastal hills. The high levels of rainfall that blow in from the western Atlantic are a boon to those seeking high yields from their vineyards, but they come at a price: the significantly increased risk of fungal problems in all but the best-ventilated sites.
Provided the risk of disease can be effectively managed, producers in coastal regions such as Lisboa (formerly Estremadura) and the Setubal Peninsula have little problem generating prolific yields. Quality can be achieved in these fertile environments only by limiting quantity through careful canopy management and judicious green harvesting. Sheltered, inland wine regions, such as Transmontano and Douro, are typically better equipped for the production of quality wines as their drier climate and alluvial soils force vines to dig deep, strong root systems. Illogical as it might seem, stressed vines make quality wines.