As your September Jockey Club packs head out the door and the beautiful spring sun shines on our vineyards, lets take a look back at a topic which helps to make sense of what’s happening in our vines right now.

Forgive me while I recap this important subject…

 

At various sites across the Adelaide Hills, vines are going through the first stage of the growing cycle called “budburst”.

Budburst refers to the period in early spring during which grapevines emerge from dormancy to produce new shoots. Small buds on the vine will now give rise to leaves and flowers. 

Budburst is brought about by changes in the air and soil temperature.

 

What are buds?

As I mentioned before, I have always struggled to get my head around this topic. And I think this is why…

The buds that will form THIS year’s growth (all the shoots, leaves and bunches for Vintage 2021) were formed during LAST year’s growing season.

Let me say that again…

When the grapevine grew all its bits and pieces (starting in Spring last year – let’s call that Year 1) it also grew all the bits and pieces it will need to start the process off again in Spring this year (Year 2). If you have a good enough microscope (and know what you’re looking for) you can also see tiny bunches in the buds! Amazing!

(and that isn’t actually quite right because the grapevine actually grew all the bits and pieces for Year 1 in the year before that! See why I get confused?!)

 

Bud formation

This is a huge topic and I could delve pretty deep and probably confuse you and me both, so I’m not going to do that.

All I’m going to say is that a bud forms (by the magic of nature!) at every node on a grapevine cane.

I ventured out into the backyard this morning to find this very sad looking grapevine to show you exactly what I mean…

That bit pointing up to the corner of the photo is called a cane. And all along the cane (spaced at regular intervals) are the nodes.

Here are some (not fabulous) close-up photos of some nodes…

And that little bump at each of the nodes is the bud. 

 

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Dormancy

We know that towards the end of the growing season in autumn, vines lose their leaves. As temperatures decrease further, vines undergo a number of processes in preparation for ‘shutting down’ for the colder months.

Vines set themselves up with the biological equivalent of ‘anti-freeze’ to ensure live tissue remains for the renewal of growth in the following spring. 

Vines are not completely inactive when dormant though. They can’t photosynthesize because they have no leaves, but they do respire (or breathe) to maintain basic metabolic functions. Their energy source at this stage is carbohydrates stored during the previous growing season, in the roots, trunk and cordons (stems/branches). Dormant vines have to exist on their stored reserves from the time they lose their leaves. The new shoot growth in spring is completely dependent on these reserves for approximately the first month.

 

Budburst

Growth of dormant buds is the result of the commencement of the expansion of the bits and pieces we talked about earlier which pre-formed in the previous season. First, the cells inside these structures expand and then eventually the cells divide and multiply.

Lots of things affect the time of budburst including…

• Air temperature
• Soil temperature (or specifically the temperature of the roots)
• Variety
• vineyard management practices in the preceding season
• time of pruning

… among others.

 

So, according to the Adelaide Hills Crop Watch report on September 8th, some vines were still dormant (Sauvignon Blanc and Cabernet Sauvignon in northern vineyards). Others (like Chardonnay in Macclesfield) had already progressed to E-L 9  (2-3 leaves separated: 2-4 cm long)!

Here is a picture (thanks to Hamilton Viticulture)…

And don’t worry if you’ve forgotten what E-L stage means. I’ll revisit that in the coming weeks.

Until then, enjoy those September club wines!

 

Wine list news

Before I go, I thought I should mention a couple of changes to the wine list!

Today we started pouring our 2023 Sauvignon Blanc. Those of you who included a bottle or two of Sauvvy in your club pack will receive this gorgeous new vintage.

We’re onto our last boxes of 2021 Tempranillo Graciano. Our next vintage, the 2022, is heading down the bottling line at the end of the month! 

Next week, Rob will be heading to Boutique Bottlers to bottle our 2021 Shiraz along with the long awaited 2023 Rosé (finally!) AND a brand new wine… 2021 Lagrein. A reminder of what that’s all about to come!

Also, keep an eye on your email for a club only heads up about our dwindling stocks of 2022 Fumé Blanc and 2022 LDR.