Weather update, managing waterlogged vineyards and additional re-entry period information

5 October 2016

The AWRI recently distributed information on Managing vineyards after a wet winter and spring. Since then, several regions across New South Wales, South Australia and Victoria have experienced extreme weather in the form of damaging winds, heavy rainfall and flooding.

The Bureau of Meteorology has also just updated its seasonal outlook and information on current climate influences, with the latest information now available at the following links:

Current predictions for the October to December period include a strong chance for above average rainfall in southeast and northwest Australia and cooler days and nights.

At any stage of the season growers can access links to weather information and useful references from the AWRI Climate Adaptation webpage.

Waterlogged soil

A flooded vineyard or heavily waterlogged soil can be damaging to grapevines. The sooner surface water is drained or pumped away the better. Useful links on managing flood affected vineyards are provided below:

The full impact of flooding may not be apparent for some time after the event so monitoring is important. Slow grapevine growth after the water has cleared can be caused by:

  • Carbohydrate depletion in vines that have been waterlogged
  • Root death
  • Soil nutrient loss from leaching
  • Cold and wet soils.

Clay soils can set hard and become compacted after the water has drained. Action such as light cultivation or mulching may help alleviate this. Cover crops or permanent sward plants will help with the drying process as they use soil moisture, provide avenues for water to drain and reduce erosion.

Additional information on re-entry periods

Further information about re-entry periods after spraying has now been added to the online version of the ‘Dog book’. For each active constituent, the range of re-entry periods specified on labels of different products is now listed, rather than just the most stringent re-entry period. In all cases, growers should refer to the label of the product being used for specific re-entry period directions. Additional information about how to interpret the re-entry period information is included on page 22 of the ‘Dog Book’.

Need help? The AWRI helpdesk provides technical support and advice to Australian grapegrowers and winemakers. Contact the helpdesk on 08 8313 6600 or email helpdesk@awri.com.au.