Vinh Nguyen from the Sydney Markets said Asian restaurants had been quick to pounce, buying the unripe and sour fruits for pickling and green mango salads.

"These mangoes have started very early this year, we normally get them in July," he said.

"Because it's such an early time of year for green mangoes they get snapped up straight away, especially in areas of Sydney such as Cabramatta.

"I've been recommending new-season green apples [to customers] as a possible substitute, but they want those green mangoes."

Speaking to ABC Rural, Mr Nguyen said green mangoes were currently selling for $10 to $12 per kilogram.