In the late 1970s Dr Richard Smart was developing theories about the role of the canopy on the colour and quality of red grapes. Those theories, Prue believed, could well be applied to the Henschke vineyards. While they were already producing high quality red wines, she believed they could do better. Initially they looked at establishing better trellis systems, which in turn led to experimenting with a cooler climate and the subsequent purchase of the property at Lenswood. There, Prue believed, less stressful photosynthesis during summer would allow flavour compounds to develop. This turned out to be right, and Henschke started winning awards and media recognition immediately.
A number of key issues must be considered in relation to soil management, such as soil structure, moisture holding capacity, and nutrient availability. There is also a need to consider such things as how to maintain good soil porosity, the bacterial activity in the soil that leads to fertility, and the effects of pH. The water holding capacity of a soil is important in dry-grown vineyards and is improved by increased organic matter and mulching. Thirty-six percent of Henschke vineyards are dry grown and the soil management techniques now used lead to the production of very high quality fruit.
Many different techniques of soil management exist. Henschke has moved completely away from mechanical disturbance and now uses permanent sward. Mulching with wheat straw to avoid herbicide treatment under the vine is used in most of the vineyards, and allows more organic matter to be incorporated into the soil and preserves soil moisture. Earthworms also open up the soil and introduce nutrients and soil ameliorants such as lime. Mulching helps to maintain the fertility of the soil without the addition of nitrogen fertilisers, which often favour the development of disease, especially botryus. A good balance of nutrients in the top 60 to 70 centimetres of soil is important for the production of premium grapes. The vineyards are currently run incorporating organic and biodynamic practices, including biodynamic compost being produced from all the winery by-products, such as grape marc, stalks and waste water, cow pit peat and 500 and 501 preparations.
The Effect of Old Vines
Australia's oldest vineyards, dating back to the 1860s, carry an aura of wonder about them and the gnarled and free-form shapes are rarely seen in other plant species of such age. For overseas industry personnel visiting these vineyards, it is a viticultural mecca.
Soon after the establishment of the Australian vineyards, phylloxera was introduced to France where it slowly exterminated most of the vineyards and beyond into Germany and Italy. Rootlings brought into Australia from the French nursery Richter led to a similar plight in the Victorian vineyards. But sand is phylloxera's enemy as it does not allow the formation of soil cracks or damp 'super-highways' between the root systems that these sap-sucking insects love. This is why vineyards such as Chateau Tahbilk's small 1860 shiraz vineyard can still exist and why, for slightly different reasons, the Vieilles Vignes of Bollinger survived the much later devastation by phylloxera in the Ay and Bouzy regions of Champagne.
Hugh Johnson makes a tiny but fascinating reference to the pre-phylloxera vines, the "Survivors of the Plague" in his latest book, The Story of Wine. He mentions that wines made from these vines "have a certain quality and depth of flavour that sets them apart…the view of Bollinger's president is that champagne from ungrafted vines (which produce small quantities of highly concentrated juice) is too 'fat' for modern tastes!" Undoubtedly this 'fatness' is the part of the texture - the extract or intensity of flavour on the palate - that we identify in the Australian red wines from the century-old vines.
South Australia has had very different infestations affecting the survival of its old vineyards.
Firstly, the fungal disease, eutypa, which is spread through large pruning wounds, causes dieback in the arms of older vines and the vine slowly rots away and becomes unproductive.
The second limiting factor is related to economic pressures forcing growers to rip out ageing vines. These low-yielding vineyards are being replaced with a more efficient trellis design particularly suited to mechanisation and better irrigation systems. The quality rating of these new vineyards depends on the vine balance, which is something many old vineyards have realised over the years. They adjust to the nature of the not-so-benevolent rainfall during the growing season and to the natural nutrient status of the soils.
The third factor is one we hope well not have to witness again - the mid 1980s vine-pull scheme - where growers were paid to rip out their vines. This mostly involved those ancient red vineyards that had developed a harmonious relationship with nature, but not with a winery purchase price.
One feature links these old centenarians - low vigour. It is a very important feature brought on by a multiplicity of factors:
- shallow soil depth
- low level of soil nutrients
- trellis style
- cultural techniques, possibly with inadvertent root pruning
- low summer rainfall (non-irrigated)
As a consequence of low vigour comes low bud numbers and open canopies, low yields and often smaller berry size. With the lower yields comes earlier ripening and full maturity - particularly important in cooler years - and a development of extract or intensity of flavour on the palate.
Their root systems are formed in the first 10 years and from then on, the roots die and re-grow using the starch reserves built up in early winter for new growth in spring. It can almost be guaranteed that within a 10-year period extremes of drought and floods will be experienced, and the root systems will develop accordingly. The wood development appears to reach a maximum butt circumference at around 30 to 40 years. After this the live wood dies off and the butts of the oldest vines have very little live tissue. Of a 20-centimetre diameter butt, about a quarter will still be alive. Practices such as machine harvesting which requires flexibility in the vine trunk are out of contention.
The cultural techniques are similar between these vineyards. They are trained either as bush vines or on a low single- or two-wire trellis and left to survive as best they can through dry summers with minimal weed and irrigation management.
Investigation into the difference between wines from young vines and wines from old vines allow one to appraise the differences in complexity and texture. Complexity is derived from the various combinations of primary fruit flavours - developed fruit flavours and flavours contributed through the winemaking and barrel-ageing. One should look at the wines analytically to distinguish the components of complexity. Flavour descriptors are useful in looking at the fruit characters, which are split into primary fruit characters and developed fruit characters.
Stephen and Prue Henschke, fifth-generation winemaking family, are working toward sustainability in their vineyards using organic and biodynamic principles. By working with the local natural environment and nature’s cycles, they are finding more natural alternatives to the energy-intensive fertilisers and pesticides to protect and enrich the land. Since 1990, the decade of Landcare, Prue has used the benefits of mulching and compost to preserve soil moisture and in building the health of soils.
Balance has also been restored to Henschke land with the replanting of original grasslands, woodlands and forests to 30% of the family’s total landholdings. In the vineyards, Prue’s work includes an inspiring ‘nursery program’ on Mount Edelstone and Hill of Grace commenced in 1986 to identify the best of the centenarian vines, with descendants planted to preserve this precious genetic heritage.
In 2009, the vineyards achieved organic precertification status, incorporating biodynamic principles. The Henschkes have always been passionate about their roles in protecting the land, the environment and the future for the next generation - particularly their children, Johann, Justine and Andreas who will be the next custodians of Henschke vineyards.
The grapevine is an extraordinary plant. The winegrape cultivars we recognise today reflect a wide range of climate adaptability - grenache loves the heat and pinot noir produces its exotic flavours in a cooler temperate climate. To produce the vivid varietal flavours, the vines need healthy soils to survive by buffering them against the extremes of summer.
Along with the minerals and water making up the physical part of the soil, organic matter and soil microbial activity are major players in the health of the soil and both are at risk from excessive cultivation and high levels of fertiliser. The inclusion of biodynamic principles in our vineyard management gives a twofold benefit - replacement of inorganic fertilisers with compost and the end of using herbicides. It incorporates the cyclic nature of our farm - from the manure of the cows and the eggshells from the chooks, to the recycling of our grape marc to produce compost, which in turn produces great wine.
The influence of the moon cycles has always been a familiar feature - Hill of Grace is always picked just before the full moon of Easter and Mount Edelstone a week or so after. Throw in nectar providing local native plants to help with pest and disease control and we have a garden of earthly delights - a food chain that replaces pest control. We have taken this one step further with our involvement in Dr Harpinder Sandhu’s Ecosystem Services project with the CSIRO, using local native plants to provide nectar for beneficial insects.
Our organics/biodynamics brochure takes you through the steps of making the biodynamic preparations, putting them out in the vineyard at the best times of the season, usually when the humidity builds up on a descending moon roughly on a monthly basis. Application of compost is on a three-yearly cycle and the covering of Triticale wheat straw mulch holds in the soil moisture and helps soil microbes, worms and fungi work the compost into the soil.
We see the nourishing of our land as a tool to connect between healthy soils and healthy people. We want to tread as lightly as possible on our land, land that is our home, our peace, our nourishment, pleasure and future.
We at Henschke are deeply committed to produce ‘exceptional wines from outstanding vineyards’. Outstanding vineyards are the product of stewardship of natural resources including soil, water and biodiversity. To maintain our heritage and enhance sustainability of vineyards, we have committed ourselves to grow wine grapes using the principles of 'ecological engineering'.
Phylloxera - the invisible hitchhiker
South Australia has the oldest commercial grapevines in the world. That is because we have never had phylloxera (fil-ox-era) - an insect that attacks and kills grapevines.
By far the biggest risk for spreading phylloxera is humans. Phylloxera can be carried in soil, grapes, leaves or anything that picks up any of these. People can carry the insect on their footwear, clothing or vehicles.
Don't spread phylloxera!
Phylloxera can be present in a vineyard for several years before any symptoms are seen. This is why it is very important not to walk or drive in any vineyards without permission - especially if you have previously been in or near another vineyard interstate. You could accidentally pick up a phylloxera insect from one vineyard and transfer it to another one.
Native Grasses in the Vineyards
A résumé of native grass establishment.
Vegetation Management Services
Barossa Old Vine Charter
Barossa Old Vine
equal or greater than 35 years of age
These Old Vines have grown beyond adolescence and are now fully mature. They have a root structure and trunk thickness that encourages diversity of flavour and character. Their worthiness has now been proven over many vintages, consistently producing the highest quality fruit for Barossa wines of distinction and longevity.
Barossa Survivor Vine
equal or greater than 70 years of age
These Very Old Vines are a living symbol of traditional values in a modern environment and signal a renewed respect for the Barossa's Old Vine material. They have weathered the worst of many storms, both man-made and naturally occurring, including the infamous 1980s Vine Pull scheme.
A Barossa Survivor Vine has reached a significant milestone in Barossa and Australian viticulture history and pays homage to the resolute commitment of those growers and winemakers who value the quality and diverse flavour structures of old vines.
Barossa Centenarian Vine
equal or greater than 100 years of age
These Exceptionally Old Vines serve as a witness to the Barossa's resilience in the face of adversity. The Barossa, unlike many of the world's great wine regions, is phylloxera free, which allowed these vines to mature into their thick, gnarly trunks and naturally sculpted forms without interference. Noted for their low yields, they produce fruit with intensity of flavour. Planted generations ago, when dry farming techniques demanded careful site selection, Centenarian Vines have truly withstood the test of time.
Barossa Ancestor Vine
equal or greater than 125+ years of age
An Ancestor Vine has stood strong and proud for at least one hundred and twenty five years. It is a living tribute to the early European settlers of the Barossa, pioneers of our modern wine industry. These Very Exceptionally Old Vines and their genetic material have helped to populate this region with irreplaceable, remarkable old stocks and are the underpinnings of our premium viticultural tradition.
These low yielding vineyards, with fruit full of intensity and flavour, are most often dry grown. They are believed to be among the oldest producing vineyards in the world.
Source: Wine Barossa
Australian Packaging Covenant Signatory
In line with our beliefs in environmental sustainability, we are a signatory to the Australian Packaging Covenant through our membership of the South Australian Wine Industry Association Mentor Program Group.
As a part of being an Australian Packaging Covenant signatory, our aim is to reduce our impact on the planet’s resources with our policy of purchasing our packaging that is, where possible, manufactured with recycled materials, or just as importantly, that our packaging is either reusable or recyclable. Below is a link to SAWIA Mentor Program Group Action Plan (2010-2015) for the Australian Packaging Covenant.