Monthly Report - July 2010
It's grey, cold and raining …
So the best thing you can do is go outside and stand in the vineyard working from one vine to the other for 7-8 hours a day. It does not exactly sound like a great time, but it does provide one with a lot of time for thinking and a lot of time to review where the vineyard is at and how all the little experiments have gone. One of the most important aspects of making fine wine is to ensure your vines are set to produce a specific volume of fruit, and the best way to do that is to control the number of buds that growth can burst forth from, hence reducing or increasing your crop.
Interestingly enough the vines which are spur pruned crop less than the vines which are cane pruned, even though the cane pruned vines have smaller bud counts. The reason for this is simply the grape bunch weights at harvest are nearly double in size for the cane pruned vines, and with this in mind the Bordeaux varieties have been spur pruned to get smaller bunch sizes and this creates more intense fruit flavors – also taking into the fact we severely thin the canopy in spring from any double canes and growth off the set spurs. Thus we have very concentrated fruit flavors through our low yields and this intensity comes through in the wines.
Photographs of cane (top) and spur (bottom) pruned vines
However, for the Shiraz and the Viognier we cane prune both these varieties as they are simple beasts for growth and you have to limit where they can grow from otherwise you will have a hedge. By cane pruning these vines I usually limit the total bud count to ~20 per vine (give or take, I may be feeling generous, or I may not), and they too are severely canopy thinned in spring / early summer to ensure yields can be controlled and that air can get through thee vigorous growing canopies. As for the other odds and sods, well I am still working them out – and that is quite enjoyable in itself as you potter away trying to unlock the potential of the vines on the vineyard.
One of the little experiments that I trialled at the end of last year’s pruning was the application of old woodchips as a ground cover. It is recognised that vitus vinifera was originally a vine that within forests and had a symbiotic relationship with trees upon which it would have used for support as it wound its way up to the light. This means the roots were often in the leaf and forest debris adjacent to the tree it was climbing, and as such this was the vines primary “niche”. To try and match this setting I applied a cover of leaf and woodchip mulch under vine and let that break down over a year – and the results have been great. Higher vine growth rates on the set spurs, higher soil development and much more organisms such as worms present in the soil profile. I am pretty happy and I will do another couple of rows – the only risk is nitrogen depletion, but this did not show up this year but I will keep an eye out as this could reduce growth quite dramatically.
Photograph of undervine mulch
To be quite honest that has been my month, one day after the other pruning in the vineyard (with my evenings filled with the images of France whizzing by with the riders on the “Tour de France”). We continue to get more and more placements of our wines in both restaurants and retailers throughout Australia and hopefully our webpage will be updated soon with all the exciting happenings in this area. The 2010 Viognier is now ready for bottling and it looks like early August for the bottling of this wine. The wine will not be released for a little while yet as with many of our wines we are trying to delay their release so as to get the wines that much more complete when drunk straight from the “crack” of the screwcap seal. But do not worry, there is still 2009 Viognier available and it is drinking just wonderfully at the current.
Also I would just like to comment that in last month’s report I did a bit of a wander through my literary favourites and compared some authors to various wines. It was really heartening to have such great feedback and to know that some of you have gone out and got the reading bug again. Thanks to all those that passed on their comments and impressions, it was much appreciated while I recovered from my few sick days at the start of the month.
A geological sojourn …
For those who have not read all the guff on the website, or have the room left to memorise all these 100’s of details, my profession through training is as a geologist. I qualified with a Masters degree from NZ in the late 80’s and scooted across to Western Australia to make my fortune – well that was the plan. I unfortunately rolled up during a lull in mining activities, but by the mid 90’s it all picked up again and has pretty much been going ahead in this state for 15 years.
With this as my background, I have taken a lot of interest in the comments made with regards to the “soil” and the “geology” of vineyards and how they are implicated in a wines “terroir”. There are many that swear by the nature of the soil as the most critical aspect and this comes through in Margaret River as the best soils for growing grapes being the “lateritic gravels”. There are others that swear by the basement rock of the soil profile and examples of this would be the Terra Rossa soils of the Coonawarra where the deep red soil (derived from windblown sands and clays) have developed over a clay and limestone (with little else). Others even go as far as indicating that only specific geological units will provide the best growing medium and the soil is treated as simply the “dandruff” on the top.
Well let me say this, they are all right, and they are all wrong.
Below is a typical soil profile. The “A” layer is basically the upper most layer enriched in organics, with the “B” layer being a combination of weathered material and some humus material, before you get the “C” layer which is often referred to as saprolite (or slightly weathered rock, it literally means “rotten rock”), and deep down is the bedrock itself.
Typical soil profile
This is the “typical” profile, and as in life, not much is typical in this world. The famous gravel soil of Bordeaux is simply very deep outwash gravels of the large river system of the Gironde and Dordogne – the soils are mixture of sand and gravel, with clay pans in areas where the river changed course and left small lakes that filled with clay over time. The soils of the Terra Rossa in Coonawarra are mostly windblown clays from the old Murray River located miles away, and these same soils are seen in other wine growing regions like the Clare Valley (but there are different underlying geologies). In Margaret River there are an absolute hotch potch of soils with deep lateritic gravels forming over very old Cretaceous clays and sands, and then being variably eroded, as well as younger soils developed over a loosely welded limestone and/or hard granitic gneisses and formed nearer to the coast. It simply is an impossible statement to define the “best” soil or geology for growing grapes, it is such a variable medium within a single paddock let alone a wine growing region that having “typical” soils for let us say Margaret River is simply misleading and dumbed down to help sell a concept.
Much of the “new world” has a hard time mimicking “old world” wines may be simply in the fact that our soils are not actually derived from the same “base material” and as such will always affect the wine grapes in subtle ways that make large differences in the glass. The difference is that Europe underwent significant glaciations during the past 150,000 years and large sheets of ice have a habit of “grinding” rock, and this ground rock “flour” and other shattered debris of the mountains of Europe (with their particular geology), sits in many of the famous wine growing areas soil profiles and provides many elemental nutrients that we do not get from our old and weathered soils in much of Australia and South Africa (without the glacial “crush”). New world wines from New Zealand and Chile/Argentina often have a dusting of volcanic ash (though there are spots without), and in America the soils are a huge mixture from outwash gravels (Long Island, NY), to the up thrust ranges of California. Every area unique and different, providing for the palette of wines we see today from same grape varieties.
So to finish. Soils are an incredibly complex layer that relates to every aspect of the environment they are in – in fact no two are identical and are one of the many factors that create the complexity that you see in any glass of wine. Do not think that any one single element is more important than any other, as the soil’s health and winemakers inputs may play bigger roles than any underlying geology, and vice versa. We have developed our vineyard grape varieties with reference to the soils, and in a couple of areas we have quite close mimics to the soils of Pomerol and St-Emilion – but are they the same? No. But we have given our vines every chance to produce wines that may carry the hallmarks of these famous French regions and that is the best we can hope for.
Rain continues to be MIA...
Another month of below average rainfall, though it is not as if we didn’t have a lot of wet days. At this time of year we often get large frontal features rise out of the Indian Ocean dumping 50-75mm in 8 hour doses before showers sweep through in a follow up giving us a further 25mm over 3-4 days. Not this year, it has been small fronts with ~25mm of rain for a day or two, then light showers following. This puts pressure everywhere – our dam is still not full, the groundwater is not running from our natural springs in the block and grass growth is a touch stunted. We have had some lovely days though and working in the quiet of the vineyard pruning has at times been quite enjoyable.
The numbers for the month and last year’s figures are provided below:
Avg Maximum Temp 16.5°C
Daily Max recorded 19.9°C
Avg Minimum Temp 7.0°C
Daily Min recorded 1.6°C
The maximum temperature range is very similar to last year, but the minimum is not as high as last year due to lower levels of cloud cover. Rainfall is ~40mm less this year in comparison to last, but we have had a very dry June and this has caused issues with groundwater recharge throughout the region – fingers crossed we get drenched in August.
Avg Maximum Temp 16.3°C
Daily Max recorded 19.1°C
Avg Minimum Temp 7.8°C
Daily Min recorded 1.7°C
Putting work to bed …
Well pruning will be finished by the first week of August and then I need to get many odd jobs out of the way prior to my departure to France for vintage in Bordeaux. My geology tasks have been sadly been ignored while I knuckled down on getting the pruning out of the road so I have 2 weeks of work to get done there. The 2010 Viognier will be bottled early August, this year 100% barrel fermented so expect a bit more body and flavor just for good measure. Some straw and more wood chips will be going out under vine and I have got some organic fertilizers to spread for the end of the month. It is busy busy down here at Blue Poles!
As always if you have any queries about what’s been written or about wine in general, do not hesitate to contact us either by email or www.twitter.com/bluepoles and we’ll do our very best to answer any question.
Blue Poles Vineyard