Green harvest (or cluster thinning, crop thinning) is when the grower removes some grape bunches in the middle of summer, before they are ripe (sometimes later), to lessen the harvest volume.
Some years ago, this was very popular. More recently, it seems less prevalent. Green harvest is often thought to result in better quality wine, thanks to more flavours being concentrated in the remaining grapes – by reducing the amount of grapes, the remaining ones become more flavourful.
A recent meta-study published on Oneo-one shows that this is sometimes the case, but not always. (This is closely linked to the idea that “lower yields make for better wine”, which is also sometimes the case but not always.) The authors conclude that many factors – most importantly climate — influence whether or not green harvest has a positive effect.
Some wine growers we have talked to say that they avoid it because the vine will react to the cutting of its “offsprings” by producing even more grapes the following year, necessitating an even more severe green harvest. They point out that it may be more important to control the yield by correct winter pruning rather than green harvest.
As so often in wine, the answer seems to be “it depends”.
Read more: internationalwinechallenge
