Page 54 - Grapevine July-Aug 2020

Around The Vineyard

Grapevines and Water

Stress, a Key to Quality

By: Dr. Richard Smart, vinedoctor@smartvit.com.au, www.smartvit.com.au
W grapes,” I am often asked. The answer principal means of regulating vine growth and phys-
“ here is the best place to grow wine and often less appreciated, is that water supply is a

I give surprises many people. I say,
“A cool desert, that is where! Deserts are typically iology to maximize fruit ripening and potential wine
quality.
sunny, but should be cool, and with sustainable
supplies of irrigation water.” A desert is preferred In brief, we prefer to have slight moisture stress
because rainfall can be a problem for quality wine during the period of active shoot growth after
production. flowering to inhibit lateral shoot growth and to
limit leaf expansion and size. In association with an
There are two significant problems associated appropriate training system, this will help maintain
with rainfall, both relating to how difficult it is to a light, porous canopy—essential for wine quality.
control, in terms of timing and quantity. Firstly, Secondly, and critically, we can use moisture stress
rainfall induces many fungal diseases on leaves, to stop shoot tip growth in the period just before
shoots and fruit, which may have direct or indirect veraison. This is essential to avoid carbohydrate
effects on fruit ripening and wine quality. Secondly, competition between the active growing shoot tip

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