WINES CAN OFTEN provide a reflection of the countries where they’re made. Take, for example, the Sauvignon Blancs of New Zealand. Even in a year such as 2020, both the country and the wines managed to triumph. New Zealand was almost Covid-free and the vintage was one of the best in recent history.

The early months of the year were less than auspicious. In the Southern Hemisphere, that’s when the harvest happens. In 2020, the Sauvignon Blanc harvest went from late February to early April; in late March, virtually all of New Zealand went into strict lockdown. But while the virus hit hard in the rest of the world, it barely touched New Zealand.

The grapes for Craggy Range winery’s Sauvignon Blanc come from a vineyard in Martinborough. Chief winemaker Julian Grounds said he had initial misgivings about harvesting under the shadow of Covid, but the near-perfect weather changed his outlook. “I did feel we all shared a collective relief when the forecasts remained so fantastic,” he said in an email.

Jill Sherwood, director of Sherwood Estate Wines in Waipara, recalled initial uncertainty as to whether the harvest would happen at all. Once winery workers were authorized as “essential” by the government, the harvest proceeded remarkably smoothly—more so, in fact, than this year’s, taking place now. The winery is short-staffed currently because some foreign workers returned home last year and New Zealand continues to restrict foreigners’ entry to the country.

Last year the Sherwood staff was allowed to travel between their homes and the winery during harvest—with documents explaining why they were on the road—while the crew at Greywacke winery in the Omaka Valley of Marlborough “hunkered down” in the winery headquarters and at winemaker Kevin Judd’s home. There was also a camper van parked on the property. It was surprisingly effortless, said Mr. Judd. “The vintage just cruised through,” he said, adding that his 2020 wines are “as good as we’ve ever made.”