After 10 years of development and Primary Growth Partnership funding, Ballance has released SurePhos, a superphosphate formulation it says will help deal to one of the big two fertiliser nutrients tagged as being the culprits in waterway degradation.
Ballance innovation leader Dr Jamie Blennerhassett said much national attention has been directed at nitrogen levels in waterways but 75% of New Zealand waterways are also classed as phosphate limited and highly vulnerable to further phosphate run-off.
“Phosphate is really something of a sleeping giant in the nutrient issue.
“We have been aware of the phosphate issue for a long time and have been working on a solution for a decade.”
Phosphate plays a big part in promoting algal growth in waterways, in some instances more so than nitrogen.
Earlier research found almost half the super phosphate applied to land can be lost to waterways through run-off and soil erosion.
Blennerhassett said SurePhos is a highly stable, gradual release product with a lower water solubility than traditional reactive phosphate.
“No one part of the formulation is totally unique but granulating it was a key part while also ensuring it has a phosphate level similar to standard super.”
Similar phosphate levels to conventional fertiliser were essential for SurePhos’s practical and commercial success.
That is particularly so in phosphate-vulnerable hill country where much of the fertiliser is flown on.
“When we set out we knew if we were to transform the phosphate fertiliser sector with a lower-risk product we would have to get something very close to what is already being used and we have cracked that.”
Cost per tonne is about $330, compared to $320 a tonne for conventional superphosphate.
“There is considerably less risk with SurePhos. With conventional product if there is a rain event up to 21 days after application the phosphate can run off.
“If the rain is the day after application the phosphate concentration in water that runs off is 2000 times higher than normal background losses. That’s like 2000 days of normal run-off in one go.”
Phosphate loss in hill country is therefore almost inevitable given 80% of it is applied in only 12 weeks of the year when rain is also more frequent.
Ballance researchers are still working on catchment modelling to determine how much phosphate run-off can be saved using SurePhos in particular catchments.
The company’s Mitigator nutrient management software can only estimate it at this stage.
“But we are developing the technology to do catchment estimates accurately.”
SurePhos is available only in the North Island after a $10 million investment in processing equipment at Ballance’s Mount Maunganui plant.
“We had hoped to have it to market three years ago but it’s been a tough process scaling up the trial volumes, at each scale-up point there was a new challenge to solve.”
The Government’s freshwater policy requires phosphate levels of .018mg/l be met.
There are very few catchments in the country where phosphate is not an issue, he said.
