Mário Nátario, the viticulturalist for Graham’s Quinta do Vale de Malhadas is also responsible for Quinta do Vesuvio, next door. At Vesuvio Mário is experimenting with pilheiros, a traditional method of planting vines in the schist walls of the vineyards. We believe this is the only quinta in the Douro to be reviving this method of planting, even on a trial basis.
A pilheiro is a hole left high in the schist walls that form the traditional patamares (terraces) in the Douro. Vines were traditionally planted in these holes and then trained horizontally over arbours, both to increase yield per hectare, and as a way of providing shade over the path below for vineyard workers.
The vineyard was first planted in the usual way, with vines growing along the front edge of the terraces. We used cuttings taken from an old, traditional mixed-planting vineyard at Quinta do Retiro in the Rio Torto Valley – in other words, there is a mixture of grape varieties in this parcel, it is not a single-varietal block.
We planted americanos (American rootstocks), with the intent of grafting in our Douro varieties once the rootstocks were established. The rootstock was planted into the hole in the wall and firmed in with soil, but we had many failures, with the rootstock simply dying rather than taking root.
Mário then tried another planting technique which is very traditional in the Douro, known as layering. In this case, Mário selected a cane from one of the vines growing in the usual fashion on the terrace above, and embedded the cane tip into the face of the wall. He bypassed the large pilheiros, and instead drove the canes into smaller openings, in hopes that the rock and soil would hold the cane securely. Sure enough, most of these canes have rooted successfully and are now in their fourth year.
But this means these vines – all indigenous Portuguese varieties – will be growing on their own rootstock. In the mid-late 19th century American grape vines were imported to Europe, and in the years following European vineyards were nearly wiped out by a mysterious disease. The problem was traced to a tiny louse, called phylloxera, that lives in the roots of American grape vines. The American varieties have developed a tolerance for this insect, but when it infested the European vines, they quickly sickened and died. Ultimately, European viticulturalists solved the problem by grafting local grape varieties onto American root stocks, and this practice has continued ever since.
I asked Mário if he was worried about phylloxera attacking the new layered vines. He said, quite simply, we don’t know yet – we will have to wait and see. We think the extreme climate of the Douro Superior, with its 35 – 40°C + summers and heavy winter rains may be in our favour as phylloxera doesn’t like either extreme heat or wet soil.
Once the vines were established, they were severed from the original vines above, and we put in a trellising system of standard wooden vineyard posts every few metres with tensioned wires to support them, and a bamboo cane for each and every vine which is tied into the wires.
At four years old, the grapes from the pilheiro vines should be interesting for making wine this autumn – wait and see!