Sunflowers thrive under stubble
GroundCover™ Issue: 16
The industry might like to see more oleic sunflowers grown in Australia but Central Queensland growers Peter and Tom Mifsud want to see how the dollars add up before committing more country to the new varieties. Oleic sunflowers have been bred specifically to have a healthy fatty acid profile for domestic cooking oils, ie: low in saturated fats to replace imported palm oil.
The brothers' Mifsud Dryland Farms have grown sunflowers for 17 years on "Wandina", north of Clermont, where they farm a total 4,800 hectares, 480 hectares of it zero-till.
Last January they zero-tilled 223 hectares to Pioneer's oleic variety Sunoleic 02 alongside 243 hectares of the same company's conventional variety Armitage. According to Peter Mifsud, the yield difference — 1.5 t/ha across the whole crop for Armitage, 1 t/ha for the Sunoleic 02 — could be partly attributed to the Armitage receiving rain at the vital flowering/filling stage (the value of which the quicker Sunoleic 02 missed because of its more advanced maturity).
Another factor affecting sunflower yield of both varieties was the quantity of stubble from the previous season's wheat crop. The crop of Batavia wheat, sown in two stages, had itself produced a variable yield and similarly variable volumes of stubble — related to rainfall around sowing time.
"In turn, as it rained over summer, the country with the heavy stubble got wetter, and that was where the sunflowers yielded best," Mr Mifsud said. "After planting in January, the sunflowers received no rain until late April and, while the wheat stubble helped retain moisture in the soil right across the crop, they were better where the wheat stubble was heavier. Those areas yielded up to 1.85 tlha."
Mr Mifsud said they had used a home-built planter with coulters ahead of Covington boxes and Gyral presswheels - to establish 45,000 plants/ha in 88 cm rows.
The sunflowers had germinated extremely well under zero-till and were six to seven weeks old before poking out through the wheat stubble.
Mr Mifsud said he and his brother had the 280 hectares under this year's Batavia wheat earmarked for another sunflower crop, again to be zero-tilled but with an improved, home-built planter incorporating a parallelogram arrangement to allow working over contour banks. "We want to plant straight rows, over the contour banks, with the eventual aim of moving to controlled traffic farming," he said.
"Zero-till gives us a wider planting window for sunflowers, with the wheat country only having to be sprayed out with Roundup and 2,4-0 to clean up the weeds," said Mr Mifsud.
Returns influence variety choice
"Even witb the $50/t premium paid last season for Sunoleic 02, I am inclined to think the Armitage had an advantage in returns per hectare," Mr Mifsud said. "With the $80/t reportedly to be offered for oleic sunflowers this year it would be a line-ball decision."
Mr Mifsud said the brothers also incurred extra transport costs with their Sunoleic 02, which had to be delivered to Retro siding, 60 ken away, while the Armitage went just 15 km to a local silo.
Last season's crop had returned around $320Iha, a better margin than for sorghum on the Central Queensland property. "Whether we grow Sunoleic 02 again this season will depend on what price they offer for it," Me Mifsud said.
Region North, South, West