Bitter pit treatment with calcium foliar fertilisers

2015–2016 | Angus Crawford, APAL and Petar Bursac, Fruit Growers Victoria | Future Orchards® demonstration trial

Bitter pit is a physiological disorder that can make apples unmarketable, and symptoms may become more obvious after fruit enters storage. This Future Orchards® demonstration trial in Southern Victoria tested calcium foliar fertiliser programs aimed at reducing bitter pit risk.

The trial was conducted at Atlanta Orchards, Moorooduc, in a Golden Delicious block with a history of bitter pit. Three treatments were compared in a large-block, unrandomised design: Wuxal Ca, a standard calcium chloride treatment using STOPIT, and an untreated control.

The work was designed as an on-farm demonstration rather than a fully replicated research experiment, so its value is in showing how different commercial calcium programs can be compared under orchard conditions. The report documents the treatment structure and the practical context in which growers were trying to reduce storage losses.

For growers, the trial reinforces the importance of managing bitter pit before harvest and evaluating calcium programs in the context of cultivar susceptibility, block history and storage objectives.