LARA WEBSTER, ABC RURAL
Results from an organic compost field trial on a Central Queensland property has seen above average pasture growth, with synthetic fertiliser use cut in half.
The trial was conducted for three months at Raglan Station, 60 kilometres south of Rockhampton.
After the first six weeks, grass from a paddock with the compost was cut, as was grass from a paddock with only synthetic fertilisers.
The yields were three to four times higher for pasture where the compost had been applied.
The compost is produced from 100 per cent green waste and mixed with air and moisture.
Some of the green waste left by Cyclone Marcia was also used.
Soil scientist Denis Baker said he could not have anticipated better results from the trial.
“Our prediction is that this soil will require less than half the synthetic fertiliser in the next couple of years,” Mr Baker said.
On an average basis, 200 to 250 kilograms per hectare of synthetic fertiliser was usually applied to the pasture.
During the trial, between 10, 15 and 30 tonnes per hectare of compost was applied, on a once-only basis.
The idea is that the organic compost restores carbon and nutrients to the Central Queensland soil, which Mr Baker said had very low organic, carbon levels.
While it would not need a re-application, it would take two to three years for the full benefits to be seen.
Mr Baker said the fact that the compost was made 100 per cent from green waste was what set it apart from other fertilisers.
“We’re actually putting in what we have taken out and also, the form of the nutrients we are putting on are slow release, so they won’t run off as synthetic fertilisers do,” he said.
“The compost actually becomes co-mingled with the soil and adds protection because it improves the soil structure.”
Farmers like what they see, but proceed with caution
Third-generation cattle producer Ryan Olive was keen to take part in the trial.
He said the transition from traditional pasture-growing techniques to organic applications was important for the future of the property.
“I think it is just a good opportunity to try and improve the soil structure and what we have always done doesn’t have to be the right way,” Mr Olive said.
“If we keep looking for new and innovative ways, something better might come along.”
While he has been impressed with the trial results, he admitted he was sceptical at the beginning.
“It is pretty hard to say that you can put 10 tonne of stuff on a hectare and you are going to get a good result,” Mr Olive said.
“When you first put it out you can hardly see it on the ground and you think, ‘this will be interesting to see if this works’ but that is what the trials are all about.
“The results will be in when we bale shortly and I think the true results will be in the next time we bale this time next year.”