New biological products assist organic move for WA winery

 

Tyke Wheatley, who operates the vineyard together with his wife, Billie Brent-White, and Billie’s parents, Drew and Rosemary, said the vineyard transition to organics now meant “they had to be onto everything a lot more’’.

 

“There is definitely a shift towards organic and it’s exciting that you have to think about whole farming practices,’’ said Tyke, the former assistant winemaker at Happs Wines.

 

Located at the northern end of the Margaret River wine region, the original ‘Glen Valley Farm’ property owned by Drew’s mother, Meg, grazed sheep before Drew and Rosemary commenced vine plantings in 1998.

 

Malbec, Merlot, Shiraz, Cabernet Sauvignon, Sauvignon Blanc, Semillon and Chardonnay grape varieties are grown over 7.5 hectares of the 39 ha property, while a further 1.5 ha is set to be planted to Grenache and more Chardonnay grapes.

 

Sheep also are still run on the property, which comprises primarily gravelly loams through to pure laterite soil that produces their best Shiraz grapes.

 

Most of Windance’s sales are made direct through the cellar door or online. A wine club that started with 100 members has since climbed to tally 550.

 

Some of the recent trials at the vineyard have focused on botrytis bunch rot, which proved problematic in 2017 and to a lesser degree in 2018.

 

“We dropped a fair bit of fruit in 2017 and a little bit in 2018 (due to botrytis),’’ Tyke said.

 

“It has been worse with the spur pruning compared with the cane pruning. We have been getting rid of the dead wood from the spurs so they are not harbouring any disease resting bodies.’’

 

Switch^® fungicide was previously applied at pre-bunch closure to prevent botrytis, however since converting to organic production, biological fungicides have been trialled.

 

“We didn’t want to lose fruit and so we tried other registered organic fungicides at pre-bunch closure and again after a rain event later, but we still got botrytis,’’ Tyke said.

 

“Trialling new products is always hit and miss, but if you commit to using something when disease pressure is moderate to high, you are hoping to see some results.’’

 

He said last season they used the new biological fungicide, Serenade^® Opti, and didn’t see any botrytis, however conditions also were drier and they had carried out bunch thinning, shoot thinning, leaf plucking and applied trichoderma (fungi) later in the season.

 

 

Containing the unique properties of the pure QST713 strain of Bacillus amyloliquefaciens (also known as Bacillus subtilis) bacteria, Serenade Opti is a formulated combination of spores and fungicidally active compounds. It acts as a fungicide by preventing spore germination and germ tube elongation and penetration, and as a bactericide by direct contact activity. The product also has the ability to activate the plant’s natural disease resistance mechanisms.

 

In addition to its use in grapevines, Serenade Opti also controls botrytis in strawberries, suppresses bacterial spot in tomatoes, capsicums and chillies, and has recently been registered for management of stem end rot and anthracnose in avocado, mango and other tropical fruit crops.

 

Tyke said they used the fungicide most importantly at 80% cap fall and pre-bunch closure, but also at 5% flowering with Chardonnay grapes.

 

“If I saw high chance of rain and humidity around flowering and fruit-set, I would use Serenade Opti. Later in the season, I would switch to a product like Botector, and for an early on-set of botrytis infection, I’d move to trichoderma sprays. I believe using a combination of different products will give the best results.’’

 

“This year we will definitely be using Serenade Opti at 80% cap fall and pre-bunch closure.’’

 

Serenade Opti was applied at 250 g/100 L of water and with a water rate of 300-600 L/ha using a Croplands Quantum Mist dual row sprayer.

 

Compatible with many commonly used insecticides, fungicides and other treatments, every application also included sulphur and seaweed fertilisers.

 

When used as directed, Serenade Opti also is soft on most beneficial insect species, including predatory ladybird beetles, green lacewings, parasitic wasps and predatory mites.

 

Tyke said they were focusing on cover cropping to enhance the beneficial insect population, which this year included a trial of buckwheat.

 

“We have lacewings, which target mealybug, and we have the buckwheat to bring in trichogramma wasps, which are natural predators of various insects.’’