The production forecast for the 2025 harvest in the Douro Demarcated Region was presented by the Association for the Development of Douro Viticulture (ADVID), based in Vila Real.

ADVID's general director, Luís Marcos, said that this was an atypical year, both in terms of the weather and the vine's growing cycle.

The flowering was good, but the vines were subsequently affected by diseases such as mildew and sunscald (in June). Therefore, according to the manager, a production drop of around 20% is expected for this harvest, with an estimated harvest of around 220,000 barrels. Last year, declared production was 274,000 barrels (550 litres).

Scald occurs when grapes are exposed to high temperatures and low humidity.

ADVID's forecasts are based on pollen collected during the flowering phase of the vines in the three Douro subregions—Baixo Corgo, Cima Corgo, and Douro Superior—and therefore do not take into account post-flowering factors, such as mildew and sunscald, which can affect harvest potential.

For this year, the estimated production potential range is between 237,000 and 267,000 barrels. However, according to Luís Marcos, "production is expected to be below the minimum forecast limit."

"This year, although the production range is not significantly lower than last year's, we expect it to be below the minimum forecast range, which is 237,000 barrels, and could be around 20% lower than in 2024, meaning values around 220,000 barrels," Luís Marcos said.

"What we've seen is that fertility—the number of bunches per vine—is lower in most vineyards in the region. The bunches are not much larger than last year; on the contrary, they are average in size, or in some areas slightly smaller," he emphasized.

The ADVID general director explained that the winter was quite dry and hot, which delayed the vine's vegetative cycle, and that the above-normal rainfall in March and April subsequently had a compensating effect on the vine's vegetative development.

Flowering was delayed compared to average, and during the pre- and post-flowering periods, there was a "very high incidence of downy mildew," a disease that affects grapevines and is present in the region but is cyclical in terms of attack severity.

"And this year, due to the summer rainfall, it had a significant impact on the forecast production potential. Growth was quite vigorous, the disease had favourable conditions for its establishment, and therefore, downy mildew had an impact on the production forecast here," he added.

The incidence of the disease is not uniform throughout the region, with the most affected areas being Baixo Corgo and other higher elevations, such as Alijó, Sabrosa, and Vila Real.

Grape picking is expected to begin around the end of August. Weather conditions in the coming weeks, leading up to the harvest, could affect production in the region and require constant attention and care for the vineyards.

Harvest forecasts are one of the parameters evaluated by the Interprofessional Council of the Douro and Port Wine Institute (IVDP) to determine the benefit, or the amount of must each producer can transform into Port wine.