Tuesday, March 31, 2009

Organic Matter - Biologic Blend vs Manures


After tough vintages the obvious reaction is to build up your vines. Many growers think of incorporating animal manure into the soil. They see piles of manure and think;  "I'm adding a lot of organic matter and goodness to the soil."

Manures are actually organic material, not organic matter. Manures need to be broken down by micro-organisms to work. Manures are unstable in the soil and as much as 90 percent of it disappears by decomposition.
A good test is to buy manure now and compost it for a year. Record the weight difference.

What you need is organic matter which is stable in your soil.

What's the difference between organic material and organic matter? Organic material is anything that was alive and is now in or on the soil. For it to become organic matter, it must be decomposed into humus. Humus is organic material that has been converted by microorganisms to a resistant state of decomposition.

Organic matter is stable in the soil. It has been decomposed until it is resistant to further decomposition.

Products like Biologic Blend are the equivalent to many tonnes of chicken or animal manure because it consists of Humic material and Organic Carbon both of which are stable and long lasting in your soil.

Friday, March 27, 2009

Over fertilising Grapevines - Q&A



Vineyard question.


Why do some vineyards re-grow after harvest? Is this a bad thing? Some growers say it is, other don't. I could of course look it up but who needs to be resourceful when you have DJ's?!


Thanks in advance.

Kristoff




We look out for signs of tip regrowth and pale looking fresh leaves after applying post-harvest fertiliser (below).

Unfortunately, in stressed vines such as the ones pictured the growers fertiliser has pushed new growth. This growth weakens the vine for next year, energy (carbohydrate) for next year is used up pushing this weak growth.

We don't think it is a good thing and is a sign of unbalanced vines.

Wednesday, March 25, 2009

Bordeaux Viticulture

The final part of my trip in France, writes Richard McGeachy, was through the enormous expanse of vineyards around Bordeaux. It is hard to fathom 125,000+ hectares of vines looks like without driving through some of it.

The trellis’ in some of Bordeaux were much like that in McLaren Vale – wider spacing’s, cordon heights and equipment – particularly around Sauveterre.


As I drove up the side of the north side of the Gironde and across the estuary to the Medoc the vineyards changed again. As did the scenery! I was in Chateau country with some of the most beautiful residences I’ve ever seen. Chateau Margaux is pictured below.


The plantings got closer, trellis heights dropped and the soils turned to coarse gravel with large pebbles like those from a river bed.



The low, close trellis’ didn’t limit mechanization as opposed to the other regions I visited.

In previous reports I saw the Rhone has limited mechanization due to its steep river slopes and Burgundy has limited mechanization because of its trellis, and in some cases by the choice of the Burgundians.

In Bordeaux the machinery was unique - for example these Braud harvesters with hoppers which would unload at the end of rows instead of into a chaser bin.


It also introduced me to some equipment I had never seen before – a machine to burn the leaves of the bunch zone. Try to imagine a gas barbeque lying on its side…


The end result…


This aims to improve bunch exposure and spray penetration. Spray coverage is particularly important in years such as 2008, when I was visiting, with mild wet late summer/early autumn period. People I spoke to were looking to pick a couple of weeks early to prevent further losses to botrytis.

It was not overly hard to find outbreaks of powdery and downy mildew in some blocks and judging by the picture below botrytis too…. Half of these drums are Scala, the other half are Redlan (chlorpyrifos for grain storage).

Rubbish always tells the truth.
This chemical usage is interesting given that the varieties in the Medoc are Cabernet Sauvignon, Merlot, Cabernet Franc and Petit Verdot. Both of the Cabernets in particular takes a great deal of moisture to get botrytis. Disease pressure must be high!

An open letter from MVGWTA Chairman Dudley Brown.

Members,

On Monday of this week, I attended a meeting with Minister for Water Security Maywald’s assistant Helen Rodwell and Chris Marles from SA Water as well as with representatives of MVGWTA and the Willunga Basin Water Company to discuss reclaimed water storage and mains water substitution. At a meeting with Ministers Maywald and McEwen twelve months ago, we (me, Jock Harvey, Derek Cameron, Leon Bignell) were assured that a new 700ML dam for reclaimed water at Aldinga would be operational prior to the irrigation season beginning in November 2009. At present, SA Water has collected tenders that are presently being evaluated that call for the 700ML dam to be built on a 40 week schedule with completion by January 2010. As the dam will not be able to be filled with reclaimed water prior to winter of 2010, no significant expansion of the reclaimed irrigation network will be possible until that time. While a tender has yet to be awarded, the “guesstimate” is for the dam to cost between four and six million dollars.

The financial cost of the heat wave earlier this year is conservatively held at $30 million dollars in lost fruit in the McLaren Vale wine region. Assuming a flow on effect of 4x to wineries, a further $120 million dollars of lost wine sales will result from this. As Willunga Basin Water Company irrigates approximately 40% of the district, it is reasonable to assume that about $12 million dollars of fruit losses came from existing WBWC customers that were not able to keep up with irrigation demands as a result of insufficient storage of reclaimed water. How many other applicants for WBWC connections were affected by their inability to connect to the network because of a lack of storage for reclaimed water is not known. However, it is probably another 10-15% of the vineyards in McLaren Vale. In any case, the price of the dam is significantly less than the damage already caused by the dam not being built. Interestingly, the CSIRO is just released research showing that where growers were able to sufficiently irrigate prior to the heat event, losses were greatly reduced. An article about this can be viewed at: http://www.abc.net.au/news/stories/2009/03/23/2523125.htm.

A few key points came out of yesterday’s meeting:

1) SA Water claims that Minister Maywald did not instruct them to have the dam operational prior to the coming irrigation season.

2) The state government claims that they have moved as fast as they could and that there is only one appropriate process to follow in putting infrastructure contracts out to tender.

3) SA Water claims to have initiated a parallel bid process to build the dam much faster than forty weeks to discover whether having a dam built on an accelerated schedule is possible.

The obvious question is “why would SA Water already be exploring an entirely different tender process if what they were already doing was the “only way” or “the right way”?” Further, when MP Leon Bignell requested a copy of this alternate tender on Tuesday, he was told he could not have one. As this would be a public document (assuming it exists), our concerns were only magnified. The obvious conclusion from the meeting was that either or both the government and / or SA Water are aware that they have dropped the ball on water storage in our region. Further, it was clear that the government feels politically vulnerable on this serious matter in the lead up to an election. The point we made to the government was that MVGWTA had remained silent or supportive when asked by the media about storage for the past twelve months on the understanding that the government would deliver on their promise to prioritize storage and deliver prior to the coming irrigation season. Given the lack of certainty provided, we indicated to Ms. Rodwell that this issue is so important to us that we could no longer remain silent and hope things suddenly improve.

Our responsibility to our members is not to discover who is not telling the whole truth here or why but to inform you of the situation as soon as we knew of it and to encourage you to make your feelings known on this matter. Directly or indirectly, this issue affects most of our members and levy payer’s businesses. We have had reports from all sectors that the light vintage has already badly affected tourism, businesses on Main Street and those of our other members.

The proposed dam is being paid for from various government agencies but the largest portion is from Waterproofing the South and funded by the federal government. Given the many problems that can not be solved in a drought, the 700ML reclaimed water storage project at Aldinga is one that protects crops, reduces polluted outfalls to the ocean, protects farm and winery incomes and, perhaps most importantly, increases drinking water to the SA Water network immediately. Compounding this situation is that the state government has still not completed its commitment to fund the McLaren Vale Water Plan for subsidizing mains water substitution for small and medium sized irrigators. Only because the Federal Government has met its commitments on this front is the plan operational. But, with no additional storage, the MVWP is unable to actually accomplish much. We are not concerned as to why the state government and SA Water have not treated this as a priority in the past, but rather to know why our water security solution is not a top priority for a government trying to manage a severe drought.

The Member for Mawson, Leon Bignell has been a constant advocate for reclaimed storage to be built over the past twelve months. For example, he wrote to Minister Maywald in October of 2008 regarding the slow progress on the storage dam and did not receive a response. He subsequently wrote to the Premier in the past month to express his frustration with the lack of response. Immediately following this, the Minister invited Leon to a “briefing” on water storage. He instead requested a full meeting with stakeholders from MVGWTA, WBWC and SA Water. This was the meeting held yesterday.

If you agree that this situation presents a risk to McLaren Vale, we encourage each of you who votes email - Premier Mike Rann - premier@dpc.sa.gov.au
Minister for the Southern Suburbs Hill - minister.health@health.sa.gov.au
Minister for Water Security Maywald - minister.maywald@saugov.sa.gov.au
MP Leon Bignell – mawson@parliament.sa.gov.au

We are quickly running out of time to get a result that will matter to the region before the next irrigation season. Your direct and immediate action on this matter will make it clear to the government that their delays are a serious risk to our livelihoods, our industry and our region.

Thank you in advance for your consideration and assistance in this matter.

Regards,

Dudley Brown
Chairman
McLaren Vale Grape Wine and Tourism Association

Oilve water stress - UPDATE 25/3/2009


In a season like we have experienced look at your rainfall and irrigation figures for the year and compare them to the list below.

Olive Growth Stage: PIRSA Impact of Water Stress

Shoot growth - Reduced shoot growth.

Flower bud development - Reduced flower formation.

Flowering - Incomplete flowering.

Fruit set - Poor fruit set, increased alternate bearing.

Fruit growth stage 1 - cell division - Reduced fruit size due to decreased cell division.

Fruit growth stage 2 - pit hardening - Minimal impact on fruit size.

Fruit growth stage 3 - cell enlargement - Reduced fruit size due to decreased cell expansion.

Oil accumulation - Reduced fruit oil content.

Wednesday, March 18, 2009

Botrytis increases after rain and dew - UPDATE 18/3/2009


Steady rain plus heavy dues in the Hills have seen an increase in botrytis. Look for slippery skins as pictured. 
Growers in the Range Road area need to have a good look if further rain occurs in Shiraz with tight bunches, and other mid to late season varieties, as their harvest is still a few weeks away. 
No significant rain is forecast at this stage but heavy dews can increase the disease. These may also require a protective fungicide.

Botrytis risk -Major Varieties

High - Sav. Blanc, Riesling, Grenache, Semillon, Chenin Blanc.

Medium - Viognier, Pinot Gris, Pinot Noir, Chardonnay, big bunched Shiraz, Sangiovese, Mataro/Mouvedre, Petit Verdot, Verdelho.

LowBold - Small bunched Shiraz, Merlot.

Very Low - Cabernet Sauvignon.

There are exceptions to these rules- different vineyard sites, croploads, canopy management and chemical strategy have an effect on the amount of rain a block can receive before showing signs of disease.

Assess your vineyard and seek specific advice as is needed.

Dicarboximides - Rovral, Fortress etc should be applied as an acidic spray tank mix (water pH less than 7) to be stable. 1kg/1000lts of tartaric acid, citric acid or similar, or a commercial buffer- tradenames include AGRI-BUFFER will acidify the water and lower pH.

PMS - (Potassium metabisulphite) dries out the bunch and can help heal berry splitting. PMS rates higher than 3kg per 1000 litres are needed and the pH of the spray solution should be adjusted to between 2.9 and 3.0 using 1.5 kg 100% tartaric acid per 1000L.

Post Harvest irrigation - Q&A

One of our readers writes the following questions.

"Post harvest irrigation?? I’ve heard these policies;


1) A deep watering to get the soil moist below the roots to encourage deeper root growth and then leave them.


2) Just water to keep the vines “ticking along” but avoid tip growth. Our moisture sensors show that our deep post harvest water is depleted. Should we be applying another deep irrigation to encourage deeper root growth or just short irrigation when needed?"


Answer - Post-harvest irrigation is important but should be limited. If you irrigate too much the vines begin to grow again and use up energy / carbohydrate that would be better spent fueling budburst next year.

The aim is to avoid an unwanted flush of vegetative growth while ensuring that the vines. capacity to store carbohydrate is not affected.

I would think it is difficult to push water down below the rootzone at this time of year. If you applied an irrigation long enough it would also make the vines regrow.

Salts are best flushed from the soil in mid winter / early spring. Generally McLaren Vale region has enough rainfall for this to occur naturally however Winter 2006 and Spring 2008 were too dry for this to occur in some sites.

They also asked;

 

"Do we want to encourage deeper root growth? We got our best Cab quality this year. I think it was because the vines were less vigorous and offered more light for flavour development. I’m not looking forward to a return to heavy spring rains which send the vines into long shoot growth requiring summer trims.



I’ve enjoyed the control we’ve had over shoot length by applying water at the optimum times. I presume that deeper roots reduce control because they have access to the deeper soil moisture and keep the vines growing when, post fruit set, a vigneron may be wanting to stop the vegetative growth. What do you reckon about that?"



Answer - You are right, dry season's do limit growth. In some sites the reduction in vigour is a positive for grape quality, in other sites vines have become water stressed and this has contributed to a reduction in crop and I would argue quality also.

Over time vine vigour is reduced as older vines lose vigour. You may vine that during the next wet Spring your Cabernet is less vigourous than it once was.

As for the deep watering. Over time vines will explore every centremetre of soil available to them so encouraging deep root growth isn't a real problem. If water is available to vines and they can get to it they will grow there regardless.

For example in 1999 Langhorne Creek had a summer flood the soil around some vineyards was washed away and the roots were seen to stretch for dozens of metres along rows and headlands.

The only factors that limit vine growth are;

Compacted soil layers - these occur naturally, or by the activity of tractors / ploughs.

Chemical barriers - soil of high or low pH. Look for bleached white soil. Carbonate (limestone) is too alkaline for roots to grow into.

Salinity.

Hope this gives some insight into our thinking.

Monday, March 16, 2009

Vintage 2009 Harvest - UPDATE 16/3/2009

McLaren Vale - The majority of picking has been completed in McLaren Vale. Grenache harvest is beginning with some blocks in the 14oBe range and showing ripe flavours and seeds. Blewitt Springs fruit include Shiraz and Cabernet Sauvignon are close to harvest ripeness and some blocks are booked in for this week.

Most Grenache we have seen the crop significantly reduced by sunburn, as pictured. The quality is strong but the yield is much reduced.

A well balanced McLaren Vale Grenache vineyard.
Adelaide Hills - In the Range Rd area Simon Berry reports he has picked Sauvignon Blanc last week and Pinot Gris. Most yields have been solid in the 4 t/a+ range he says, and where they have been down, the reason has likely been a reduced fruit set issues rather than heat issues.

He expects Pinot Noir will be bit over 3 tonne/acre.

Chalk Hill Viticulture has harvested some Pinot Noir on Wednesday morning which went 13.1oBe, pictured below.

Pinot Noir in the Adelaide Hills - note the wind damage / late season leaf yellowing.
Late season varieties in this sub region, Cabernet and Shiraz are likely to be a few weeks away, with some growers reporting that they expect a late season for these varieties.

Wednesday, March 11, 2009

Botrytis signs - UPDATE 11/3/2009

Botrytis bunch rot in a McLaren Vale Riesling vineyard.
Look out for signs of grey mould in tight, thin skinned vineyards. Levels are low as of this week, but mould could increase with wet weather.

Heat on new vines - Messenger Article

Heat on new vines

10 Mar 09 by Sarah Garvis


McLaren Vale Vine Improvement Society (MVVIS) chairman James Hook and cuttings and operations manager Darran McLaaren.

Heat-tolerant grapevines from southern Europe are being imported to McLaren Vale in a new attempt to help local winemakers overcome climate change and drought.

During last month’s 40C-plus heatwave, local vineyards recorded crop losses of up to 75 per cent, making this the worst harvest in years for many growers.

McLaren Vale Vine Improvement Society (MVVIS) manager Darran McLaaren said approximately 40 new varieties were being imported, in conjuction with the SA Vine Improvement Society, from Spain, Italy, France and Portugal.

Mr McLaaren said Sercial from Portugal, Aglianico from Italy and new types of Syrah from France will be released this season, with others in quarantine to be released in two to three years.

“They use less water and are better able to stand up to the heat,” he said.

“We, as grape growers, need to look further into what is grown overseas that may be suitable to our changing climate.
“Varieties that are grown in some dry, warm climates may prove vital for our future.”

The trial vines will be planted first at Kapunda, before the sticks or cuttings are propagated into pots and distributed to vineyards in McLaren Vale.

Mr McLaaren said this would allow MVVIS to produce greater quantities of the new vines to release to the industry.

MVVIS chairman James Hook said the next few years would present significant financial and operational challenges to grape growers and winemakers.

“Climate change and water availability will require serious consideration of new grape varieties and rootstocks,” he said.

Mr Hook said Chalk Hill, d’Arenberg and Olivers Taranga were “big innovators in new varieties” in McLaren Vale.

Olivers Taranga winemaker Corrina Wright said the winery had a much lower crop this year due to the heat.

“We’re getting about 1500kg to the acre whereas we’d normally get 3000kg to the acre,” she said.
“We use recycled water, less chemicals and go by touch and feel rather than the calendar, but it certainly doesn’t make us immune to the impacts of the heat.”

Ms Wright said the winery was trialling heat-tolerant crops, new to Australia, including the Spanish black grape Tempranillo.

Friday, March 6, 2009

Rust Mite seen in the vineyard - UPDATE 6/3/2009

Rust mite bronzing on leaves and close up detail (below) - 6/3/2009.

Look out for these symptoms. A rust or dark grey colouring on leaves. Note any signs of this in your diary for next treatment next spring.

Thursday, March 5, 2009

Splitting and Botrytis - UPDATE 5/3/2009

Botrytis - note the grey mould inside the bunch.
Botrytis – Levels have remained low in monitored vineyards. Some splitting has been seen in tight bunches of Sauvignon Blanc.

If you are in the Hills check for any signs of this and any grey mould as seen above.

Fine weather has prevented any significant spread. Most white vineyards in the Adelaide Hills are now within 1 weeks of being harvest ripe. With further dry weather botrytis should not be an issue where harvest is expected in the next 7-10 days.

Growers with late season, eg McLaren Vale Grenache or in cooler sites should continue to monitor for signs of botrytis especially after any rain or heavy dews.

McLaren Vale Harvest Estimate


Based on the information we have at hand we can have an estimate of the total tonnage crushed in the McLaren Vale GI.

Some blocks have picked as high as 4 tonnes to the acre, 10 tonnes to the hectare, but more commonly they have been between 1.5 tonnes and to 2 tonnes to the hectare, 3.7 tonnes to 5 tonnes to the hectare.

Our estimate is 35,000 tonnes for the region, this is slightly up from vintage 2007 but down 25,000 tonnes from vintage 2008. The record crush for McLaren Vale was in 2004 at approximately 72,000 tonnes.