Keith Mugford openly admits that he is obsessed about the weather, especially during the growing season. It comes up in conversation a lot,  which is hardly a surprise when considering how much is riding on it. With Keith’s insights, we can illustrate this in two ways…

“In order to keep the vineyard safe from fungal disease, we monitor the weather to decide how and what treatments we should use. For example, our primary cover comes from Sulphur, a topical treatment for powdery mildew, that washes off with too much rain. We have to keep a close eye on the amount and timing of precipitation and if we get too much, reapply a treatment, even if only a few days have passed since the last.

Another way of understanding the focus on the weather is to consider temperature and how its fluctuations affect us. In the end, the fundamental quality of the wines we make, from any variety, entirely dependent on how well the grapes ripened and which is a direct result of the daily temperatures we receive.

We look back fondly at our early vintages and marvel at the innocence of the time. Of course, we tried hard to make the best wine we could but we knew so little about what we were dealing with.

Each year was a new adventure and we sailed blindly into it, with very limited experience to use as a guide as to what quality and style we might expect. Of course, we had the excellent modelling by Dr John Gladstones, who’s work showed we could anticipate good quality in an average Margaret River season but that was nothing like the detailed understanding of the vineyard we have today.

With 48 vintages at Moss Wood under the belt, we now approach each season with clearer ideas. We monitor the vine growth stages and temperatures and can gain significant insight into what style of wine we might be heading for and what management techniques we can apply to give the best outcomes. It’s a lot different to the old days and no wonder we are obsessed by it.

There is, however, a delicious irony. No matter what we know about the season we’ve experienced to date, we can never know beyond a day or so what the future holds. We’re never as smart as we think we are because Mother Nature loves to deal us wild cards. It’s the game we’re in. It is said the price of Liberty is eternal vigilance and this has been re-worked in the name of many causes so perhaps we could fashion it into a viticultural statement that the price of high-quality wine is eternal vigilance?”

“If we were lucky enough to be able to order up our growing seasons, we’d go to that web page and click on 2017-18 just about every time, although we’d probably hesitate over 2000-01 for a moment or two. It would be a tough choice deciding which of the two was better and since we’re talking nerdy stuff, let’s make the comparison. The mighty 2001 enjoyed a season where the average temperature was 19.4°C, and Cabernet Sauvignon took 126 days to ripen to 13.5°Baume, receiving 1210 hours between 18-28°C. The 2018’s numbers were 128 days to achieve 13.6° Baume, after 1197 hours. To give some idea of how similar these are, the average temperatures can vary between 18.7-21.1°C, days vary between 100-130 days and hours between 1000 and 1250. As an aside, these numbers might provide an insight into why Moss Wood Cabernet Sauvignon wines taste similar but never exactly the same.

For consumers, it’s what’s in the glass that matters and the same is true for us. As much as there is some wonderful consistency between those two years, when we decide on the picking time for any variety, it is always based on the flavours in the grapes. By monitoring the seasonal conditions, we were hopeful there would be exciting quality in 2018 because the temperature comparison with 2001 told us so. However, we made the decision to harvest when the flavour profile was at its best not when the numbers lined up, although we can see it’s no coincidence. All this to tell you the 2018 growing season is one of the very best.

We received above average rainfall for 2017 and to keep the vines well-watered, 267mm fell during the growing season, including a very handy 25mm in early February.

Flowering conditions were largely benign, without serious interruption by heavy rain or low temperatures. There were no problems with disease and we kept hungry birds at bay by applying our nets. This meant yields were good with Cabernet Sauvignon up 18%, to 8.67 tonnes per hectare and Petit Verdot up 9% to 6.06 tonnes per hectare. Cabernet Franc let the side down slightly, with a yield reduction of 11% to 5.21 tonnes per hectare. Each variety marched comfortably through to ripeness on or a day or so later than average..

Having got to this point, readers may be asking themselves did we get the job done properly in the winery? Fortunately, the answer is yes. As is so often the case with the great years, the wine essentially made itself. For all 3 varieties, after hand picking and sorting, the destemmed fruit was put into small open tanks, seeded for fermentation with multiple yeast strains and hand plunged 3 times per day. Skin contact was a very typical 2 weeks, after which the wine was pressed to stainless steel tank for malolactic fermentation. Upon completion, each batch was racked to 228 litres French oak barrels, where it stayed for 30 months.

In October 2020 all barrels were racked and blended in stainless steel and the final blend consists of 92% Cabernet Sauvignon, 4% Petit Verdot and 4% Cabernet Franc. Fining trials were carried out and it was no surprise that none of the agents improved the tannin balance, so the wine remained unfined. It was then sterile filtered and bottled on 2nd November, 2020.”

“Margaret River has developed a tremendous reputation for its Chardonnay wines and yet the variety’s contribution to the total vineyard area in our region doesn’t really reflect this. Consumers may also notice the relative scarcity of Margaret River Chardonnays on retail shelves and restaurant wine lists. The reasons for this were front and centre for the 2019 vintage.

While we have generally very good conditions for grape growing, our maritime climate can be a blessing and a curse. We enjoy a wet but mild winter which means the temperatures do not drop low enough to keep the early varieties, and Chardonnay in particular, in a long dormancy.

For example, as I’m writing (at the end of August), the Moss Wood Chardonnay is now well into budburst. However, the wet and cold weather hasn’t finished and, in some years, can run through until December. Those sensitive new shoots are at risk of being damaged by strong winds, hail and even frost. Add to this the variety’s relative softness, which makes viticulturists joke that it’s the one which will catch a cold, and it becomes clear that the Margaret River and Chardonnay do not always get along.

To put it bluntly, in 2019 we saw all the things that can go wrong. Frost is not an especially common event here but Moss Wood’s topography does make us somewhat frost prone. Cold air can collect in our little valley and will sit over two of the Chardonnay blocks and on very cold nights we get frosts. Serious frosts occurred in 1981, 1982, 1987, 2017 and 2018, although we can get light frosts in just about any year. The ’81 event was very nasty, coming as it did in mid-October, wiping out the bottom third of the Moss Wood vineyard. With it went more than 80% in each of the Chardonnay, Semillon and Cabernet Sauvignon blocks in that area.

In 2018, on 15th September, we had a frost of almost the same scale but were lucky in some respects, because Cabernet Sauvignon had not been through budburst so we were spared the worst. However, two of our Chardonnay blocks copped a nasty hit. The temperature at our weather station, well above the cold zone, dropped to 0.3°C. Ouch! Losses in both were 90% and Clare and Keith became media personalities for a week or so after it was picked up by the press.

What followed was everything we don’t like about a Margaret River spring. Over the 50 days during which the Chardonnay flowered, we had 14 days of rain and 15 days when the temperature dropped below 8°C, all of which disrupted the process. The only thing we didn’t get was hail, so perhaps we should be thankful. The resulting yield of 3.61 tonnes per hectare was a dismal 47% down.

After flowering things progressed relatively easily but Mother Nature had one last trick up her sleeve for 2019 – the birds. The redgum flowering was virtually non-existent and the silvereye birds developed a voracious appetite for grapes. We applied nets to keep them off and had some success and the losses were minimised but the already small crop meant we had to pick and sort every bunch as carefully as possible.

After this tale of woe, readers will be amused to know the season was absolutely brilliant for ripening conditions and flavour development. Temperatures remained moderate right through the summer and Chardonnay received only 6 hours where the mercury exceeded 33°C. It made its way lazily to full ripeness over 121 days, using up 1130 hours between 18° and 28°C from flowering to harvest, a week longer than normal, crossing the finish line on 25th March at a ripeness of 13.1° Baume, exactly its long-term average. We could not have been happier with how it all tasted.

The fruit was hand-picked, sorted and whole-bunch pressed and the juice was settled in stainless steel for 48 hours. The clear juice was then racked to stainless steel, with a small inclusion of solids and seeded with multiple yeast strains for primary fermentation. At the half way mark, the fermenting must was racked to wood to complete the process. All the barrels were 228 litre French oak and 50% were new. After primary fermentation the wine then underwent malolactic fermentation and upon completion all barrels were racked to stainless steel, blended, analysed and adjusted for acidity and SO2.

The finished wine was then returned to barrel, where it stayed until the end of June, 2020. At this point all barrels were racked and blended in stainless steel and fining trials were carried out. The wine was fined with bentonite, for protein stability and then sterile filtered and bottled on 13th July, 2020.”