Yield increases of 39% over three years
Ciampa Produce, which annually grows more than 12,000 tonnes of onions has increased average yields from 80 tonnes/ha to 111 tonnes/ha over the past three years.
They believe an important contributor has been an improved fertiliser strategy.
This included the introduction of BioAgPhos to the program in 2010 and demonstration of the value of a more consistent release of P over the growing season.
Phil Toy of BioAg says progressive operators like Ciampa Produce are reaping the rewards of putting measurement into their business and tracking inputs, outputs and the returns from investments.
In the Ciampa Produce case, measurement to refine strategies includes routine fortnightly sap and petiole testing through the onion growing season.
Daniel Mead, first called on his brother Glen, director and agronomist with D&M Rural, to undertake a testing program to identify any barriers to healthy uninterrupted growth.
“For quality onions supplied to a discerning national market we seek good control of the variables in growth,” Daniel said.
“Soil and moisture conditions plus the weather of course come into the picture but we had been particularly interested in getting the nutrient supply right and with Glen’s services we were able to find peaks and troughs in phosphorus.”
The previous fertiliser program for P was primarily based on superphosphate.
Glen‘s testing identified P levels as being very high early in the life of the onion plants, followed by significant leaching away of the nutrient to form a trough.
Responding with another superphosphate application to top up meant another peak in P followed by yet another trough.
“Introducing reactive rock phosphate, with less immediately available P, in a single early application as BioAgPhos, ironed out the peaks and troughs,” Glen said.
“We’ve taken out the leaching and variability and avoided going back to the crop for another application of phosphorus.”
Although the total cost of nutrient applications has been steady at about $500/hectare the new program based on measurement and the tracking of responses has meant improved performance.
Glen is satisfied about the agronomic benefits of BioAgPhos and believes that while there have been several factors contributing to the improved performance, ranging from use of water retention products to soil and water management, this input is the one that can most clearly be correlated with the outcomes.
Note that while BioAgPhos has proven to be the ideal means of providing P through the length of the growing season it also provides this nutrient in the critical early stages when there is high demand for P.