A Cold May Slowed Down the Vines: Winemakers Warn of Continuing Drought and Hailstorms

Key facts:

• A below-average cold May in 2025 slowed the growth of grapevines in South Moravia and failed to bring the soil the moisture it needed, leaving persistent soil drought.
• This spring was the sixth driest since 1961 in the Czech Republic, with an average of 117 mm of precipitation – just 76 % of normal – and South Moravia showing the country's largest rainfall deficit.
• Winemakers expect the vines to flower around their traditional early-June timing, but warn of continuing drought and an increased risk of hailstorms.

Starý Plzenec, 5 June 2025 – A below-average cold May has slowed the growth of the vines and, on top of that, failed to bring the soil the moisture it needed. According to meteorological measurements, soil drought therefore persists in South Moravia, and it may continue to affect the vineyards negatively in the months ahead.

"May put the brakes on the plants, and so this year, for the first time in several years, we expect the vines to flower at the traditional time – roughly around St Medard's Day," said Petr Ptáček, Viticulture Manager of BOHEMIA SEKT, adding: "Compared with the rapid onset of the growing season in recent years, development is returning to the rhythm known from the last century, which may contribute to a more even course of the wine season and a smoother harvest."

Drought Is Not Easing, and Moravia Remains Below Average

Drought, by contrast, remains a major complication. According to data from the Czech Hydrometeorological Institute, this spring was the sixth driest in terms of precipitation since 1961. Across the country, an average of 117 mm of rain fell, or 76 % of normal. South Moravia traditionally lags well behind this average and shows the highest rainfall deficit in the Czech Republic.

Drought hits young plantings with shallow root systems hardest, as they are more sensitive to weather fluctuations. "When the roots at a depth of 50–70 cm find no moisture, the plant would rather slow its growth and invest its energy in saving its leaf area. This is later reflected in lower grape sugar content and a smaller yield," Ptáček explains.

Storms with Hail as a Further Threat

Alongside the drought, this season also brings an increased risk of sudden weather extremes. Already in spring, some parts of South Moravia were hit by local storms with hail that damaged the plants' leaf area. If similar events were to recur during the period when the berries are setting, there is a risk of uneven ripening of the grapes and higher losses at harvest.

"In our conditions, the situation changes from year to year. Based on developments so far, however, we fear that storms and hail could come more often this year than we are used to," Ptáček concludes.