A MOVE to custom, controlled-release nutrition is improving fertiliser efficiency, better meeting plant nutrient demands, saving applications and boosting yields and fruit uniformity for Bundaberg watermelon grower Mark Piper.
Situated in the Hummock area near Bundaberg, Mark grows seedless watermelons as well as Jap pumpkins.
Up until recent years, he applied Nitrophoska base fertiliser or conventional fertiliser blends, before fertigating crops with a large range of soluble products including calcium nitrate, potassium nitrate, MKP and MAP.
Simon Andreoli, agronomist with BGA AgriServices at Bundaberg, said local growers traditionally had problems with nitrogen losses with conventional fertilisers due to rain.
The Pipers now use their own, eight-month Ferticote controlled release blend from Barmac.
Soil testing has helped to tweak the blend, which has been called "Ferticote Double Basal" because it is used for two watermelon crops.
The first planting in August-September is harvested at the end of November, while the second planting at the end of January is harvested in April.
Following the application at bed forming, soluble fertilisers are fertigated as required and are increased for the second crop.
The Ferticote Double Basal, which uses Haifa’s Multicote controlled-release technology, comprises eight per cent nitrogen, 5pc phosphorus and 16pc potassium, plus sulphur, calcium and magnesium trace elements.
Multicote products incorporate a special polymer coating that allows a slow, continuous release of dissolved nutrients to the root zone at a soil media temperature of 21 degrees.
As soil warms up, the release rate increases consistent with plants’ growth rate and nutrient consumption.
Other factors such as microbial activity and soil moisture do not affect the release rate.
"With conventional blends, excessive moisture can make them play up," Mr Piper said.
“With the controlled release, it’s regulated and we can easily apply calcium nitrate if it’s needed.
“We like the low N and high K and the calcium.”
