The Long Dry Finish- Frost on the vines

We had a touch up from frost this spring as the overnight temperature dropped to -2.7 degrees overnight 27th September.
So, this seems like a good time to talk about the effect of frost on vines.

The vines we grow for wine are Vitus Vinifera, of which there are between 5000 to 10,000 varieties originating from the broader European region.

These vines have varying tolerance to cold, but generally are able to withstand winter dormant temperatures as low as -15 degrees. As the buds begin to swell in Spring there is still some tolerance to frost but the tolerance narrows to near zero once the green leaves appear.

When the water within the leaf cell freezes it forms ice crystals that puncture the cell walls leading to instant cell death.

Grapevines have Compound buds that house the Primary, Secondary and Tertiary buds. The Primary bud is dominant and is the first to push out in the spring. If the Primary bud or the shoot it produces is damaged the Secondary bud pushes out and the same applies for the Tertiary, it will push out if the Secondary bud is damaged. The Secondary bud typically produces one bunch of grapes whereas the Primary bud has two or sometimes three whilst the Tertiary bud doesn’t produce fruit.

When frost occurs early such as this year the vine can be managed to compensate for the less fruitful Secondary buds. However, when frost occurs late e.g. November/December there simply isn’t enough season left to ripen the fruit from the Secondary buds.

Typically, we will shoot thin to reduce the yield and to allow airflow through the canopy. So, this year I’ll leave a few more shoots to get the desired number of bunches per vine followed by leaf thinning to allow airflow through the canopy.

Patina Newsletter

For news on our new release wines, events and other winery information, please fill in the form to receive our seasonal newsletter.

Item added to cart.
0 items - $0.00