A Short Forward
Prior to reading the harvest report, I felt it apt to mention that all recorded data used to compile this and previous harvest reports has been generously made available by Hortec. However, I have made mention on our website www.richardkershwwines.co.za of the importance of differing subzones within the Elgin region and from this report onwards I will draw specialised data from 3 other weather stations sited in and around the Elgin Valley. These are located on Paul Cluver Farm, Elgin Orchards and Highlands Road band. Whilst we hope to gain more insight by using more data and being able to join the dots more effectively, it may be well worth mentioning some broad generalisations that exist within Elgin as we unpack the climatic data.
Firstly, the Western part of Elgin (herein referred to as the Lake District) tends to be more prone to the Northwester wind and thus receives higher rainfall in winter. It tends to also receive the most rainfall per annum (1000-1150mm) of all the areas. Being closer to the Sir Lowry’s Pass means that it receives the warmest temperatures during the Summer months, although the Palmiet River moderates temperatures, especially at night where cooler temperatures are recorded. It could be deduced therefore that this area tends to experience the highest diurnal range. The Groenberg Mountain subzone, north of the N2 highway has lower rainfall – 700-800mm per annum, but as it bears the brunt of the Black Southeasters (wind), receives higher summer rainfall as a percentage of its total rainfall. Temperatures during the summer are slightly moderated by these winds and the area tends to cool down rapidly at night. The Highlands subzone has the highest altitude and experiences reasonable rainfall (800-850mm per annum) but importantly tends to have much cooler maximum temperatures in the Summer due to the elevation, although generally cools down less at night.
Despite a short movement in August/September 2012 to suggest that climatic conditions may veer towards El Niño after 2 years of La Niña, the El Niño Southern Oscillation has ebbed back to neutral conditions, i.e. neither La Niña or El Niño has endured to date, and will likely persist in this way through the coming summer. Although this means that neither particularly dry nor wet periods will subsist, weather extremes can still occur.
The former effect of La Niña had been to reduce winter rainfall and lower temperatures. A return to normal would be expected and in 2012 the winter rainfall measured was 678mm higher than either 2011 (567mm) or 2010 (644mm) but spot-on the long-term average of 680mm.
Taken across the subzones, the Groenberg, Lake District and Highlands received 343mm, 600mm and 453mm respectively of Winter rainfall – just below the average but not significantly. Cold units (CU) during the winter however were higher than average with 1124 CU recorded in the Lake District compared to 1082 (2011/2012) and 924 (2010/2011); similarly Groenberg experienced 1099 CU and Highlands 1131 CU. This made the 2012/13 winter one of the coldest in decades possibly as a result of a lag phase from the back of La Niña but yet reminiscent of the typical old Cape Winter of yore.
As such the result was fabulous winter dormancy for the vineyards and the rainfall, which fell consistently rather than in downpours, meant that the vineyards were well-nourished and underground water was plentiful for the forthcoming season.
The cold weather pattern experienced in Winter continued through into Spring with some very cold nights and cool days recorded – in the Lake District every day during Spring went below 15ºC and many below 10ºC – the cold units in September were a whopping 403 compared to 334 (2011) and 239 (2010).
Maximum daytime temperatures were also lower with only 20 hours over 30ºC recorded during Spring in the Groenberg Mountains area compared to 50 hours, already low, the previous year.
The rainfall during Spring although higher than the previous 2 years at around 185-205mm across all areas, was less than the long-term average of 299mm.
The effect of the cold weather in Winter delayed budbreak and prolonged cold weather in Spring meant budbreak occurred over a longer timeframe – for example, in the Groenberg budbreak took over 46 days compared the average of 20. However, the long budding meant that it was very complete and its uniformity boded well for the harvest.
In turn this led to a much later flowering, up to 5 weeks in some areas, from the 26th November, compared with 22nd October on average. The flowering on the Syrah was excellent and relatively quick whilst the Pinot Noir and Chardonnay, although fine, was spread out over a number of weeks.
The prevailing Cape South Easter was less evident earlier in the season (September/October) but as Spring wore on it began to cause problems, particularly on exposed sites. Late shoot growth on some of the reds led to some damage in these areas.
The Cape South Easter continued to blow throughout December and January and unusually into February resulting in the vineyards remaining extremely healthy even after short downpours of rain. The prediction was of a reasonably high crop yield in beneficial condition.
Veraison for the Syrah was late but quick (29th January to 7th February) enabling the Syrah to pick up some lost ground from the flowering.
As harvest beckoned however, these downpours became more frequent taking the form of black Southeasters, in particular in areas such as the Groenberg. Rainfall in February and March was 71mm and 27mm respectively, a jump on the fairly wet 2012 (19mm and 41mm) and the drier 2011 (7mm and 7mm).
Even areas such as the Lake District experienced a wet February (51mm) and March (30mm) but still a tad off the 2012 rainfall (26mm and 84mm respectively).
This resulted in not just some of the earlier ripening varieties like Pinot Noir and Sauvignon Blanc suffering from potential rot issues, but also some of the mid ripening varieties too, like Chardonnay. However, there was a patch of finer weather from mid-late March, which led to most of the Chardonnay being picked in good weather. However, as April commenced, the heavens opened again and in areas like the Lake District, 147mm of rain fell compared to the wet 2012 (105mm) and 2011 (97mm) against drier 2010 (30mm) and 2009 (35mm). Despite Winter setting in prematurely, most of the Syrah came off just in time at the start of April circumventing potential issues. By comparison, the Groenberg subzone only received 84mm, about average, and any rot problems here were avoided.
As has been mentioned in previous posts, February in Elgin tends to be cooler than March and January and 2013 was no exception. There was however a pick up in temperature at the end of February but it is interesting to note that the temperature never exceeded 35ºC in both January and February.
Analysing the data (see Table 1) more closely reveals some interesting information: in the Groenberg only 2 hours of sunshine were recorded in the entire 2013 season where the temperature exceed 35ºC as compared to 15 hours in 2012, a figure itself somewhat lower than the long term average (LTA). Remarkably, only 82 hours of 30ºC or greater were recorded compared to the LTA of 220 hours, substantially less than the 180 hours recorded in 2012, itself noted as a cool vintage.
The warmer Lake District figures were equally low: 205 hours over 30ºC noted, of which 24 exceeded 35ºC, whilst in the Highlands subzone a tiny 23 hours reached 30ºC or more and zero exceeded 35ºC!
Furthermore what is intriguing with the data sets (see Table 1), is that precipitation in the growing season (Spring and Summer), 391mm, actually exceeds the Winter figures, 343mm, in the Groenberg subzone and is not that different in other subzones, adding weight to the notion that Elgin behaves more like Northern European climatic models.
Table 1 Climatic Data Summary 2012/13 Season
|Growing Season Total||343||600||453|
|Winter Cold Units||Measured using Richardson System||1099||1124||1131|
The overall message was that the harvest was expected to be late and sugars accumulation slow. As such a period in March of warmth, the time when the mercury did top 30ºC more regularly, meant that ripening did catch up to some extent for the whites and in particular for the reds, and the grapes achieved good phenolic ripeness being picked at similar times to 2012 which overall was around a week later.
The long phenolic ripening period meant again that no excessive sugars were picked up and more moderate alcohol levels were achieved.
In the cellar, lighter berry weights meant that the juice recovery on the whole-bunch pressed Sauvignon Blanc and Chardonnay was 580 l/ton as compared to a norm of 600 l/ton. The total and extractable anthocyanins for the Syrah were lower than for previous years with averages of 516mg/l (Extractable Anthocyanins) and 1217mg/l (Total Anthocyanins) compared to 680mg/l and 1632mg/l respectively in 2012, and more akin to 2008, and as a consequence meant a little more punch down’s were required to extract the colour and tannin. The skin and seed tannins were also the lowest for some time (30% lower than the past 6 years) resulting in softer textures and smoother more approachable tannins, which will make for a very elegant, more ethereal wine. However the maturity potential is the highest denoting that the grapes were picked closer to optimal ripeness than in the past. The phenolics are also lower with the Phenolic Index (TPI) at only 39 compared to the last 6 years of 44, 53, 52, 54 and 52, suggesting that the wines will be less astringent with more delicate tannic frames, and no finings will be required.
In conclusion, it is perhaps surprising that the overall yields ended up a shade lower than the LTA but up from the reduced 2012 crop. It is worth bearing in mind that the previous (2012) season was altogether a cool season throughout resulting in excellent quality grapes. 2013 has essentially continued and exacerbated this trend resulting in what may be superb wines.
In 2013, the combination of cool Spring weather gave plenty of time for the buds to break, a uniform budbreak and flowering period with wind only starting later (and starting strongly) enabling healthy grapes with only minor damage to some of the shoots.
Peak temperatures were noticeably lower than the LTA but more importantly than even 2012, which itself has been considered a cool vintage, a cool February and January enabled good fruit set with slow and steady flavour development, although the depth of colour is less than 2012. The steady tannin accumulation in the reds also meant that structurally these wines are fabulous and will allow for long ageing yet their delicacy will also make them approachable in their youth.