Organic viticulture is defined as the application of organic agriculture practices to produce grapes and wine of the highest quality.
This is done by managing the vineyard holistically with a deliberate design and management of the production system to minimise the need for human intervention such as spraying and cultivation. In other words, the first choice of organic viticulturist is to use knowledge of the basic requirements of the vine to provide just the right growing conditions and to manipulate the physical and cultural conditions in the vineyard, rather than intervening with a chemical.
Certified organic grape and wine production in Australia first appeared in the 1980’s with wineries such as Botobolar (Mudgee, NSW) and Robinvale (Sunraysia, Victoria).
As in other industries, there have always been organic producers. Some grape growers have stuck firmly with ‘the old ways’, possibly out of suspicion or because they refused to spend money on chemicals. They may have been lucky enough to survive because they lived in a favourable area, or perhaps they were very dedicated growers who observed the weather closely and relied on the ‘smaller toolkit’ which organic growers are permitted to use.
However, certified organic producers are permitted to use some ‘naturally occurring’ substances, such as sulphur and copper, pyrethrum, neem and even newer products such as the biological caterpillar control, Bacillus thuringiensis (sold under various brand names such as Dipel® or Novasol®). Because even these chemicals may be toxic to other life, organic producers use even these tools carefully and as a last resort.
The first choice of organic viticulturist is to use knowledge of the basic requirements of the vine to provide just the right growing conditions and to manipulate the physical and cultural conditions in the vineyard.
All committed organic growers, regardless of the crop, are aware of the importance of soil fertility and management for the health of the plant. Good disease resistance is founded in sound nutrition, based not just on NPK, but also upon attention to trace elements, humus, water holding capacity and soil-water management. Knowledgeable producers can manipulate these things in a variety of ways, and rely as much as possible on management actions rather than fertility or pest control inputs.
Of all plants, the vine is perhaps the best example of how small changes in soil conditions can be demonstrated to reflect most directly upon the end product.
In organic cultivation, nutrients are provided by composted animal manures and other ‘organic’ waste or by pelletised animal manures, naturally occurring finely crushed mineral fertilisers (lime, dolomite, gypsum, potassium and phosphate rock etc.) and a range of manufactured products such as blood and bone, liquid seaweed (kelp) and fish emulsion products. Certified organic growers are permitted to use a selection of trace element products including substances such as borax and natural (non-EDTA) chelated products.
Organic growers use watering regimes, careful selection and timing of cultivation, mulches and cover crops to further manipulate soil conditions.
They are also likely to use varietal selection, location choice, trellis design and environmental enhancement to their advantage.
Varietal selection is important to ensure vigorous growth. For example, Cassegrain (Port Macquarie, NSW) planted Chambourcin vines, a non-vinifera variety, because they are in a summer-rainfall area. Non-vinifera vines are not susceptible to powdery mildew.
One of the key strategies for any grower seeking to reduce chemical inputs is to understand the influence of sunlight on the vine. Row orientation, trellis design and the use of extra lifting wires, vine training, pruning and leaf trimming are all used to open up the vine to penetration of sunlight. This practice is very effective at reducing the frequency of disease treatment and the quantity of any permitted chemical used to obtain a good coverage. Once again of all plants, vines most obviously demonstrate the effect of good sunlight exposure to the quality and character of the end product.
Sulphur and copper readily achieve disease control in some areas, if the basic requirements of the vine have been provided. Some organic producers use home made products such as Casuarina tea or biodynamic preparations such as 501.
Most organic growers use sulphur for powdery and sulphur and copper for downy mildew. New products are becoming available, as alternatives to these proven, but sometimes overused treatments. Tricodex, for example, is an Israeli made biological control for Botrytis. Organic growers may not use genetically engineered organisms, but otherwise generally adopt the best practice biological control options for their industry and location.
Organic growers train themselves to accept some level of pest attack and apply the concept of a damage threshold before any treatments. Apart from the economic wisdom of this strategy organic growers understand that you cannot have a biological control without a pest presence. Sometimes the beneficial insect (ladybird, lacewing, parasitic wasp etc) will not reach effective control numbers until the pest population has built up. If growers reach for the spray tools too early, they may never know what would have happened had they done nothing.
Environmental enhancement is a means of manipulating the general environment of the vineyard to encourage natural predators. It can include management of the under-vine and inter-row ground cover or of windbreaks and other ‘non-productive’ areas, to ensure that shelter and food are available for beneficial organisms. It is especially important for many insects (parasitic wasps, hoverflies etc.) that flowering plants are available during the full length of the growing season, as the adults of these species often feed on pollen and nectar. They fly into the crop to lay eggs that hatch into the parasitic larvae. There are now commercially available cover-crop seed mixes that are designed to bring nectar sources into the inter-row area.
Light spraying oils (white oil) are permitted for disease and pest control.
The best form of weed control is to have a healthy, established cover crop to smother weeds. Straw (or compost) mulching is used at Penfolds organic vineyard (Clare, SA) and others, but it does have a high establishment cost. Careful mechanical control of weeds/cover crops using discs is acceptable if based on strategic timing to reduce negative effects, such as pulverised soil, erosion and compaction. Under vine weeds are controlled by brush cutting, hand hoeing or cultivation use of a Clemens under-vine weeder or similar tool. The Clemens weeder is highly regarded as an effective under vine treatment where mulching is not effective or where frost control is critical. Hand hoeing remains a useful strategy and if outbreaks of problematic weeds are controlled while they are small in extent they can prevent significant work later.
Certified organic grape and wine production in Australia is distributed across the country from Margaret River (southern WA) to the Hastings Valley (mid-coast NSW). It includes small producers such as Highbank at Coonawarra (SA) or larger producers such as Penfolds at Clare. It is possible to produce excellent quality wines according to organic standards, and some of the wines produced by:
- Cassegrain (Hastings Valley)
- Temple Brewer (Langhorne Creek, SA)
- Settlers Ridge (Margaret River)
- Penfolds (Clare Valley) are an excellent example.
A number of smaller quality producers are appearing, including Random Valley (Margaret River) and Martins Hill (Mudgee).
The export market for organic wine is growing rapidly. Australian organic wine is sold in UK, USA, Japan and Sweden, with smaller but developing markets in other Germany and Asia.
Not all producers of organic grapes and wine are certified, but certification is required for an organic claim on export produce and the domestic market for organic product does expect to see certification marks.
The Australian certification agencies that have grape and wine producers are the:
- National Association for Sustainable AgricultureAustralia Ltd (NASAA)
- Biological Farmers of Australia (Australian Certified Organic)
- Biodynamic Research Institute of Australia (BDRI), which administers the Demeter symbol in Australia.
The stories of these and other producers can be found on our web site, together with technical pages on how to apply organic methods to soil management; pest and disease control; and winemaking.
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