Adapted from Ellen’s Garden World, published 1 October 2014

The grape harvest has begun in Switzerland, but many of the best growers are holding off for a few more days.

As the author of the first book in English on Swiss wines in 20 years (Vineglorious! Switzerland’s Wondrous World of Wines), I’m out in the vineyards talking to growers and taking photos.

This week’s lesson comes from Philippe Bovet, one of the country’s top wine producers, who insists that people pick fruit in general, and grapes in particular, too soon.

The only way to tell if grapes are at peak ripeness is to taste them daily.

Some growers in canton Vaud are picking their Chasselas grapes this week, but for Bovet, that’s probably 10 days too early.

“I don’t measure the sugar anymore – I just keep tasting them,” he says, vine parcel by parcel, to ensure they are picked at the optimum moment.

Chasselas skin should melt in your mouth and not leave a slightly bitter aftertaste. As they ripen, these grapes become more translucent when the sun shines through them.

Bovet’s team began picking Chardonnay and some Chenin last week for his sparkling wines, but the rest of the grapes are being given more time.