Saturday, May 26, 2012

Pruning Assessment

We use the pruning season to assess how we are going to set up vineyards for next vintage. The number of buds left at pruning time will determine the shoot density through the next growing season. High shoot densities lead to shaded canopies that in turn can produce low grade red fruit at harvest.

Shoot density is defined as the number of shoots per metre of canopy. This number varies depending on the type of trellis system, for example, the ideal density for vertical shoot positioned (VSP) trellis system  in the Adelaide Hills is 10-15 shoots per metre. For semi-sprawling canopies, shoot density can reach levels of up to 30 shoots per metre.

Here are a couple of reference vineyards we have worked on. 

1. Trying to improve Shiraz quality.

This McLaren Vale Shiraz vineyard that was shoot thinned as our trial for Vintage 2012. This vineyard was thinned to approximately 20 shoots per metre. This was an attempt to let more light into the vineyard canopy.

For Vintage 2013 we assessed this vineyard as having moderate vigour.

The vineyard has moderate vigour, with canes 60cm-140cm.

Before pruning.


After pruning.

The most common pruning system used throughout McLaren Vale is “Spur Pruning” whereby last year’s canes growing from the cordon are pruned back to two nodes to form a ‘spur’.

If the vines were more vigorous, then in an attempt to balance vegetative growth and increase cropping potential, we could have retained more buds. This can be done using a Finger and Thumbpruning system. It is similar to the spur pruning system but rather than reduce two canes to a normal two bud spur, the upper cane is retained and shortened to around 4 buds.

Pruning detail. This shows that it was difficult to leave vertical spurs.
2. Maintenance Pruning

This vineyard grew a Shiraz fruit to a high grade in Vintage 2012. They are aiming for a repeat this season by keeping their canopy open by close pruning making sure spurs are upright and the buds per metre are 18-20.

After pre-pruning.

Pruned - note the straight spur positioning.

This vineyard is leaving 18 buds per metre and will produce a low to moderate shoot density for Vintage 2013. This pruning job was assessed as being adequate to set the vineyard up for A-Grade target.

Thursday, May 24, 2012

Mixed rainfall outlook for southeastern Australia

The Australian Bureau of Meteorology is reporting a drier than average winter for South Eastern Australia. This itself is not an issue for horticulture. As long as there is enough soil moisture for grass germination, covercrops will grow and nutrients will cycle through the top soil.

The main concern is for horticultural crops if lower than median winter rainfall occurs over June, July and August. Winter rain is needed so the subsoil will be flushed of sodium that has built up over last summers irrigation season.

The BOM says in its 23/5/2012 update;

probability of exceeding median rainfall - click on the map for a larger version of the map

"The southeast Australian outlook for winter 2012 shows the following:
A drier season is more likely for southwest NSW, northwest Victoria and much of SA. This outlook is mainly influenced by warmer than normal waters in the Indian Ocean. 
Over much of southern and central SA, parts of northwest Victoria, and southwest NSW the chances of receiving above normal rainfall are between 30 and 40%. In other words, the chance of below normal rainfall is between 60 and 70%."

Experience from dry seasons, notably Vintage 2007 and 2008, shows that soil moisture during spring is critical for vine health and in some respects quality. If vineyards are water stressed too early in their life cycle the results are detrimental to both yield and grape quality.

Growers should consider a drought strategy if winter and then spring does prove to be dry.

Monday, May 14, 2012

McLaren Vale Vine Improvement Catalogue and Order Form


Dear Grapegrower and Winemaker,

The 2012 McLaren Vale Vine Improvement order form is attached.

Cuttings are $49.00 for 100 sticks.
Cuttings of exotic varieties are $69.00 for 100 sticks.

McLaren Vale vine improvement is a not for profit organization, lead by volunteer grapegrowers and winemakers tasked with providing clean planting material and maintaining a phylloxera resistant rootstock nursery. We also specialise in providing material for grafting. You can specify this on the order form if you are grafting.

Cuttings for Grafting are $79.00 for 100 sticks.

We offer a $2- per 100 bundle discount for members. Why not join today? A membership tax invoice is attached.



Regards,

James Hook

Volunteer Chair
McLaren Vale Vine Improvement Soc. Inc.
m: 0400 656 350
p:  08 8323 8339
f:  08 8323 0181

Thursday, May 10, 2012

Organic Wine in the EU.


The European Symbol for Organic Wines.
The European Commission has voted to implement standards for the production and labeling of organic wine.

Up until now there has been no approved process for the production of organic wine and therefore it has only been possible to label wine as "produced from organic grapes". These new regulations will allow wine to be certified as organic which for the first time will allow consumers to be confident that they are purchasing a fully organic product.

The new laws have been voted on but have not yet been published - when they are they will become law.

Saturday, May 5, 2012

Close Planting of Grapevines - Q&A

Hi DJ's,

What is your take on close planting? Under what conditions would you consider it, especially in relation to Cabernet and Merlot?

Thanks,

Ryan J


Thanks Ryan,

Great question. We will try to answer this as best we can. Planting density sparks a great deal of debate, especially with some South Australian nursery sources, or the international high flying Michel Rolland claiming that it improves wine quality.

Where does this thinking come from?

Background.


There is no single reason for high planting density - simply planting closely does not ensure greater concentration of fruit flavours, nor does it ensure the greater root-competition induced improvement of flavours. Conversely, we are not aware of any research that shows planting widely degrades the quality of the resulting wine. It all depends on the site and the vineyard management.

High density planting comes from having narrow rows and close vine spacing.

Vineyard in Bourgogne's Côte d'Or départment.
In Europe there is both high density and low density planting.

The Bourgogne currently plants on a basis of 10,000 vines a hectare (1m x 1m) for Premier Cru and Grand Cru - though there are as many variations on this theme as there are vineyard owners, with some planting "out" to 1.3m x 1m. and some "in" to 1m x 90cm. These vineyards are of course planted to the variety Pinot Noir.

In the Bordeaux regional AOC's, the traditional home of Cabernet Sauvignon and Merlot planting densities range from 4,000 to 10,000 vines per hectare.

The trellis’ in some of Bordeaux are much like that in McLaren Vale – wider spacing’s, and high cordon height – particularly around Sauveterre.
High density in Bordeaux with 1.2m row width.

Sources reporting on pre-phylloxera Bordeaux vineyards had extremely dense plantings - up to 28,000 vines a hectare - but we don't know whether these densities produced better wines. The best source is considered to be the early 20th Century wine scholar George Saintsbury and he could not differentiate between pre and post phylloxera wines.

Balancing this are vineyards in Spain where they  entirely consist of goblet pruned, free-standing vines - all quite old and sufficiently widely spaced that tractors can pass all four ways through the vineyard, for cultivation purposes.

Spanish low density vineyards in Rioja, like those pictured, are considered to be some of the most valuable in the world.
Tempranillo in Rioja Alavesa.

McLaren Vale vineyard c.1970.
Tio further this many of the original McLaren Vale vineyards were similarly planted as low density vineyards. Some of these are still in production and make excellent quality wine.

 

Climate plays a part.


Conditions in south eastern Australia and high rainfall parts of western Europe are very different. Also in the New World vineyards we have the flexibility, in most years, to irrigate - and this alone is a massive change to the root environment and to productivity compared to the 'Old World' where irrigation is limited.


European experience is not to be sneered at - but this is not directly applicable to Australian sites. It suits the cool-climate and shallow soils of say Bourgogne - but this does not necessarily apply to the deep, rich silt loams of say Langhorne Creek - or the volcanic soils around Stellenbosch in South Africa

Close planting at 0.8 m vine spacing with unilateral training.

Narrow row width = high density.

Spacing of the vineyard rows is more straightforward.

If each row of vines represents the machines in your "factory" then the greater number of factories you can have, the greater the production from the vineyard. Therefore the greater the number of rows, the greater the potential yield.

The vine is acting on intercepted sunlight so it is important to minimise shading of adjacent rows. Smart and Robinson (Sunlight into Wine), came up with the coefficient of canopy height plus 10% as the row width (1.1H).  Just note that you can't go too close together as it makes tractor operations difficult. In practice rows narrower than 2.6 meters begin to limit tractor operations.

A McLaren Vale vineyard with 2.4m vine row width. Note the vineyard has difficulty with routine operations like fertiliser application and weed control because the rows are too narrow for contractor machinery.

Should you plant Cabernet and Merlot in high density?


To directly answer the question, Cabernet Sauvignon and Merlot can be successfully grown at low to high densities, they are in many cases including in Bordeaux.

Climate, and vine vigour are the factors to consider.

If you have a low vigour, dry site then close planting may not be the right way to go. We would look to planting these closely if the climate and soils resembled European conditions - which they can do in the Adelaide Hills, an in some other areas.

Whichever way you go what we would aim to achieve, in all cases, is a "balanced vine". We have a strongly-formed opinion that overly stressed vines make stressed wines - and a balanced an healthy vine will make good wines - almost regardless of other factors.

Narrowing vine rows can be a good option of increasing vine density, but tractors are going to limit how narrow you can go.

Friday, May 4, 2012

2012 Almond Harvest - Tonnages are light, but the future looks alright

The 2012 Almond harvest has now been completed. It has been light in tonnage, but the future for the almond industry looks positive.

Almond Board of Australia chief executive Ross Skinner says the high Australian dollar is making it hard to compete against the United States.

"The Australian dollar above parity certainly places us at a disadvantage against the US industry - that's our major competitor on export markets," he says.

Picking started in February in the Riverland and 2 weeks later on the Fluerieu Peninsula. Our sources in the Riverland reported that yields were down by 15% on last season. Allied to this prices were down due to the high $AUS, which lead to lower returns to growers. 

Yields on the Fleurieu were average with groves reporting 1-1.25 tonnes per hectare.

Despite lower yields and lower returns for growers the long term future for almonds looks bright. The Australian almond industry has undergone rapid expansion, becoming one of Australia's fastest growing horticulture sectors. The industry has been  tapping into rising demand in Asia and elsewhere.
The industry has identified India and China as priority development markets.

Split Almond.

“India has a very strong heritage for cooking with almonds… Indian mothers give their children almonds before they leave for school because they believe almonds promote mental strength,” Sam Freeman from DJ's notes.

Fleurieu Almond Harvest.
Sam said ongoing almond nutrition and irrigation research is need to keep improving orchard yields and quality.

Thursday, May 3, 2012

Olive Disease - unknown late season fungal infection.

Late season marking on olive fruit.
This is an unknown disease on olive fruit found in Barnea on the Fleurieu Peninsula south of Mt Compass. The markings looks similar to Lepra fruit rot caused by Phlyctema vagabunda but Lepra fruit rot is not recorded in Australia. 

"The symptoms on the photo appeared to Peacock spot disease. Infection and development of olive scab disease, peacock spot on olive fruits caused by Fusicladium oleagineum." says Dr Vera Sergeeva from - http://www.olivediseases.com/ ."It is always better to see samples and check spores under microscope."

SARDI have published their olive disease guide - http://www.sardi.sa.gov.au/__data/assets/pdf_file/0006/46707/olive_fruit_poster.pdf

Wednesday, May 2, 2012

April Weather Summary

April Rainfall 

 

April long term rainfall averages.
2012 = 27.8 mm

The April recorded rainfall for McLaren Vale was approximately equal to the median rainfall.

This is compared to the long-term average of 40.1 mm on 8 rain days, and the median rainfall of 33.6 mm. By comparison, during April 2011, 13.6 mm was recorded. April 2010 was the last April in Adelaide with above average rainfall with 49.6mm.

Most of the month saw only small rainfall totals from weak cold frontal systems. Much of the rainfall observed for the month came from a series of cold fronts around a strong cold air mass in the third week of the month. This event also produced significant totals in the Adelaide Hills in the persistent moist westerly airstream, resulting in totals for the month in this region being closer to average than on the plains where totals were typically only 50% of average.

Rainfall totals for April 2012 across the plains typically were ranged from 15 to 25mm with higher totals in the 25 to 50mm range in the Adelaide Hills. The wettest location for the month was Mount Barker where 49.2mm was recorded for the month, most of that occurring on the 22nd and 23rd of the month.

Temperature


Much of the month was very much warmer than average with maximum temperatures up to 6 degrees above average in the first week. Daytime temperatures remained about 2 to 3 °C above average for the month as a whole, despite a cooler burst of weather near months end associated with a strong cold air mass and sequence of cold fronts.

More Info  

 

http://www.bom.gov.au/climate/
























































































Tuesday, May 1, 2012

Seasonal Rainfall Predictions


A dry winter is predicted, why?


The southeast Australian outlook for May to July 2012 shows a drier season is more likely for southeastern SA. 

This outlook is strongly influenced by warmer than normal water temperatures in the Indian Ocean.

If this winter season is drier than median this has a significant effect on the horticultural crops. These crops have finished their season (Grapes, Olives, Strawberries, Almonds and Stonefruit) and winter is an important period in their cycle. Winter rainfall is needed to assist in flushing the soil of salts that build up over the growing season.

Above - Over Tasmania, western and central Victoria, and southeastern SA the chances of receiving above normal rainfall are between 30 and 40%. In other words, the chance of below normal rainfall is between 60 and 70%.

BOM Climate Report 26/4/2012 -

The southeast Australian outlook for May to July 2012 shows a drier season is more likely for Tasmania, Victoria, and southeast SA. This outlook is strongly influenced by warmer than normal waters in the Indian Ocean. 
Climate indicators across the tropical Pacific Ocean remain neutral (neither El Niño or La Niña). Climate models surveyed by the Bureau of Meteorology suggest that the tropical Pacific Ocean will remain at neutral levels at least into early winter. 

All major indicators of ENSO, including cloudiness, trade winds, the Southern Oscillation Index (SOI) and sea surface temperatures in the tropical Pacific, lie well within the ENSO-neutral range. Over the past week, the SOI has returned to values not seen since April 2010. 

Some, but not all, climate models note an increased risk of El Niño conditions evolving during winter or spring. Historically, about 70% of two-year La Niña events are followed by neutral or El Niño phases. 

The Indian Ocean Dipole (IOD) has limited influence on Australian rainfall from December through to April. Model outlooks currently suggest neutral conditions are the most likely scenario heading into the southern winter. 
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For more information visit -  http://www.bom.gov.au/climate/ahead/rain.seaus.shtml