I’ve been invited to “harvest day” at a one-acre vineyard I didn’t even know existed – right on the banks of the Yarra River in Hawthorn – and what I keep asking myself is what the hell do I wear? Do I don picnic-appropriate linen, or prepare to get sweaty and dirt-covered in workwear? I split the difference and go with denim.

As I book an Uber, it’s crystal clear the “urban winery” thing is no joke. It’s less than 10 minutes from my place in Abbotsford. But, cruising down a quaint backstreet in Hawthorn, neither my Uber driver nor I can see any signs of a vineyard. It’s just cute house, cute house – ah, cute house with buckets piled full of grapes out front.

The bucket-hauling crew is in shorts – I should’ve worn shorts – and they point me in the direction of a set of open gates just off the street.

Stepping through, I see the hidden inner-city vineyard in all its glory. And it’s surreal – a couple of minutes ago I was driving past Ikea and now I feel instantly transported someplace else. The whole block slopes down towards the river and each row of vines is illuminated by the beaming midday sun.

General manager Jason Buesst tells me these grapes don’t give a lot of notice as to when they’re ripe for the picking. But today’s the day – the brix level is just right. Translation: “[That’s] basically the sugar content inside the grape,” Buesst says. “As the grapes ripen they develop a higher sugar content, and as a winemaker there’s a sweet spot you’re waiting for. When the brix level hits that … you have a short window of time to pick the grapes and press them. Leave it too long and the wine will end up being too high alc.”

With family and friends mobilised for the impromptu harvest, Buesst walks me through rows and rows of 23-year-old chardonnay, pinot noir and nebbiolo vines – the grapes end up jiving together in the Coppin Sparkling, which Hawthorn Estate is best known for.

We bump into the owners – Radek Sali, former CEO of vitamin company Swisse, and his wife Helen – and while I’m yet to pick a single grape they greet me like an old friend.

They’re proud of their crop. And Radek tells me the City of Boroondara – which encapsulates suburbs such as Hawthorn, Kew and Camberwell – “was the pre-eminent wine region in Australia in the 1800s, with over 100 vineyards along the Yarra”.

“We could have been the next Burgundy!” he laughs, only kind of joking. “The climate here is so perfect for wine, these grapes come up as a great sparkling.”

We pick a few handfuls of nebbiolo off the vine. These grapes are tiny, with a rich colour, and they actually look like a completely different fruit to what you get in those supermarket handbags. There’s so much damn flavour here too – when I taste one, I get an immediate, all-in-one hit of sweetness, acidity and cheek-puckering freshness.

When the grape-picking ends, about 50 hungry harvesters mill around tables of food with flutes of the just-released 2017 vintage Coppin Sparkling in hand. Each vintage yields only 2500 bottles or so, Buesst says.

Produced in collaboration with the Macedon Ranges-based Kilchurn Wines, it spent three years “on lees” (meaning it was left in contact with leftover yeast particles to add texture and weight). It’s two-thirds chardonnay, giving it a light floral character that’s offset by the rich and complex pinot noir and the raspberry-like nebbiolo.

Wine-tasting in the very vineyard where it all began is always something special – but when that’s just four kilometres from the CBD, it’s even more so. And while I can’t help but wish this place was open to the public, on the flipside, knowing it exists right under our noses is almost enough for me.

Find a Hawthorn Estate stockist here.