AFTER a tough start the walnut grove established at Koondrook by Bryan and Tracey Goble is starting to bear fruit.

After surviving the long drought and low water allocations, the Gobles expect to spend four weeks harvesting their sixth crop and are hoping it will reach 30 tonnes.

Yields vary according to maturity, with the 13ha of trees ranging in age from six to nine years old. Mr Goble said the younger trees were expected to produce about 2 tonnes/ha.

He hoped for up to 5 tonnes/ha from the oldest block.

"About 4 tonnes/ha is what we intend to achieve, and anything better than that is going well," he said. "Last year the industry really got knocked around badly with blight - growers had losses of 15 to 100 per cent - but this year's crop is looking quite good."

Several years ago, when the irrigation season started with a zero allocation, the Gobles aggressively pruned many of their younger trees so they would need less water.

This stunted their development, but the trees have since staged a remarkable recovery.

Mr Goble said they chose to grow walnuts after considering several enterprises that might be suitable for the 120ha former dairy farm.

"Walnuts came up as being a potential for import replacement," he said.

"They were suitable for this area - the water and soils were suitable - and the climate gives a longer growing season and reduces blight, so that's what attracted us. And we weren't interested in continuing dairying."

Most of the trees are of the popular chandler variety, with about 10 per cent cisco pollinators.

The nuts, which are enclosed in a green inedible husk, are removed from the trees by a mechanical shaker. The Gobles then make three sweeps up and down each row with a purpose-built harvester that sucks the fallen fruit from the ground and drops it into a bin on the trailer behind.

The nuts are sent to Koraleigh, north of Swan Hill, where Quality Walnut Producers - the Gobles are part of the group - has a processing facility.

There, the nuts are cleaned, hulled, dried, graded and marketed to wholesalers in Melbourne. The Gobles also sell their nuts at the farm gate, farmers' markets and in local shops.

They employ one full-time worker, while Mr Goble continues to run his plumbing business.