The less water we need

by PHILIP WHITE - This was published in The Independent Weekly in 2007

While we’re talking water, I was surprised to read Cara Jenkin’s piece in The Advertiser linking Riverland grape irrigation to salt. There was the clever irrigation R&D man, Dr. Tapas Biswas, and Fosters viticulturer, Gioia Small, promoting a salt management regime that has cut annual irrigation requirements from 10.4 megalitres per hectare to 4 megs. One meg used to be called one million litres. Salt is still NaCl, which is unleashed by irrigation.

Let’s get this in perspective. Baz White, - Gomersal Wines, Barossa - was on the phone immediately. “Jeez, Whitey”, he said. “The River blokes got it down to four megs!” Since the day he planted in December 2001 Baz has used 0.65 megs per hectare per year. He has twenty hectares all up, uses bugger all poison, and has a list of some very famous Barossa names keen to get his fruit. In sharp contrast, I recall some whingeing from upriver about the lack of buyers of any sort.

Heat makes exotic plants very thirsty. Rice, cotton, oranges, vines – you need oceans of water in the desert. The Barossa’s not cool, but it’s a lot cooler than the River.

“Four to six megs per hectare would be about right for responsible commercial use up here in a year like this” says Riverland viticulturer and lecturer Darryl Lang, who made a brilliant organic Second Dune Ruby Cabernet a few years back, and hasn’t irrigated at all this year.

“It’s amazing how my vines stay alive”, he says. “But I wouldn’t suggest to anybody that they should follow my example. If I was serious about making commercial wine in 2008 I’d be watering right now. But in a drought like this the evaporation loss is awful. Even those growers who have decided to ‘mothball’ their vines and grow no crop this year would be using four or five megs I reckon.”

Michael Waugh, who’s just added another perfect 100 Parker points to his phenomenal tally at Greenock Creek, in the Barossa, uses about the same amount of everything – that’s bugger all - as Baz White. “Some of my vineyards never get any irrigation”, he said. “But if I do buy them a drink, it’s about 0.6 of a meg per hectare - thirty litres per vine. There’s no point in letting them die of thirst, but most of my watering is mainly a vehicle to get some nutrient down to their roots.”

Next day I tasted Paxton barrels. Paxtons manage 300 ha of vines including their own, and have begun replacing the old chemical spray and big irrigation with Rudolph Steiner’s biodynamic methods. The first wine from their 20ha Quongdong Farm vineyard near McLaren Vale, after just one year of the new management regime, was probably the most vividly flavoured, wholesome ’06 SA red I’ve seen. The bio stuff jumps at you. It’s like a new variety.

“We’re limited to 1.1 megs per hectare if we’re using aquifer water on conventional vineyards”, says David Paxton. “But sometimes we use much less.”

“And you know Whitey”, says Paxton viticulturer Toby Bekkers, “the more we build up the humus in our soil with the biodynamic preparations and mulches, the less water we need”. There sure wasn’t too much water in that Quongdong Farm shiraz. I’ll warn you when that one’s imminent. It’ll be famous.

Earlier, I’d stood with Andrew Mitchell in his House Block biodynamic riesling vineyard in the Skillogalee Valley, Clare. There was misty rain, and you could smell the gamy reek of the roos we’d disturbed. The wine is brilliant and vibrant, with the sort of banana and lemon pith aromas I’d usually associate with expensive German rizza. The soil didn’t smell of banana, of course, but for a weathered old mix of dolomite, magnesite, sandstone and quartzite, it certainly had plenty of life buzzing in there since it’s been getting its doseage of Steiner’s moonjuice. Andrew has two enormous mulch heaps moulderin’ away on the headlands, ready to add to that veritable plum pudding once they’ve decayed enough.

“Logic says that the more biomass we can get into this ground, the less water we’ll need”, he said. “We try to keep pretty calm about it, but it’s really bloody exciting!”