Primitivo

Primitivo is genetically identical to Zinfandel, and both descend from the Croatian variety Tribidrag. The name comes from primativus, early-ripening — it is one of the first varieties picked in Puglia, sometimes in August.

Despite the shared DNA, Primitivo and Zinfandel taste noticeably different, which is a useful demonstration that a grape's identity is only part of the story. Puglia's heel-of-Italy climate, its old bush-vine plantings and its winemaking traditions produce a wine that is darker, more savoury and more earthbound than California's: black cherry, dried fig and plum, with liquorice, dried herbs, leather and a distinctly warm, spiced character.

Manduria in the south is the reference zone, where the alberello bush-trained vines grow on red soil over limestone and produce concentrated fruit at low yields. Gioia del Colle, higher and cooler, gives a fresher and more structured version.

The grape shares Zinfandel's habit of ripening unevenly within the bunch, which leads to high sugar in some berries and consequently high alcohol; fourteen and a half per cent is standard and sixteen not unusual.

There is a long tradition of sweet fortified and semi-sweet versions in Puglia, and Primitivo di Manduria Dolce Naturale has its own DOCG.

The legal position on the names is settled: the varieties may be labelled with either name in the European Union, but in the United States they are treated as distinct for labelling purposes.

The relationship with Zinfandel is a useful lesson in how much of a wine is the grape and how much is everything else. Identical DNA produces a Californian wine that is jammy, bright and oak-influenced and an Apulian one that is earthier, more savoury and more tannic, because of soil, training, climate and cellar tradition.

The alberello bush-training used in Puglia matters more than it sounds. The low, unsupported bush shades its own fruit from the fierce southern sun and reduces water loss in a region with very little rain, which is why old plantings survive without irrigation on ground that would kill a trellised vine.

As a buyer, the practical marker is the zone. Manduria gives the densest, most alcoholic and most traditional wines; Gioia del Colle, a couple of hundred metres higher, gives fresher and more structured ones. Both are labelled Primitivo and they are noticeably different drinks.