Published on 09 Jan 2019
Now that the new year has started, we are only about 5 weeks from the start of vintage 2019! In about a weeks time, we will see the start of ‘veraison’. This term describes the photosynthetic process of sugar development. The berries will begin to swell in size and start to develop the deep purple colour as they ripen. Hydration of the vines remains critically important during the hotter months to ensure they do not defoliate, and to maintain the canopy. As we pass through veraison, the irrigation times will be shorter in duration, but interval times will be closer together, as deep moisture from (lack of!) winter rain drys out. This is to ensure the vines are not over stressed, while at the same time safeguarding that the fruit does not take up too much moisture, which can dilute flavour and colour. Typical target size for Shiraz berries is about 13mm diameter, which gives a good ratio between skin and flesh. What some people may not realise is that the juice from red grapes is actually white! The colour comes from the skin! Hence, if the berries are too large from too much irrigation, colour (and flavour) will be diluted.