Walnut season is just around the corner, and we’re keen to know more about this incredibly versatile addition to any baked good. David William from Omega Walnuts, with 64 hectares of farmland spread over two different WA-based orchards, knows all about this.

Tell us about Omega Walnuts.

Omega Walnuts is the largest commercial grower and processor of walnuts in Western Australia. It also ranks in the top five in terms of size of orchard and production in the country and is the largest grower and producer of organic walnuts in Australia.

Our smaller orchard at Nannup commenced some two decades ago, and our larger orchard at Manjimup, where our processing centre is located, commenced some 14 years ago.

Why walnuts?

Walnuts are among the oldest foods known to man, and there is evidence of walnuts being consumed over 8,000 years ago. There is a wealth of scientific and medical evidence of the benefits of walnuts not only to the heart, but also to the brain. The recommended balance of Omega six to Omega three is 4:1, and that is almost precisely the balance found in walnuts.

What goes into maintaining a successful walnut farm?

We pride ourselves on the taste of our walnuts, and that involves rapid collection at harvest, refrigerated storage, and a unique cracking and packing facility on the farm that aims to preserve the valuable oils within the kernel. It is not only the taste, but also the health benefits that are preserved the more the oils are retained. We are also able to send our nuts to market rapidly, as we are in control of our own cracking and packing. Many chefs must agree, as we have twice won the prestigious Delicious Award in WA voted on by chefs!

Like all horticulture, there is a great deal of husbandry involved. As well as orchard management (pruning, grass sowing, etc.), we carry out regular soil and leaf inspections on each block and feed our trees a range of nutrients through products sourced by our suppliers from many countries. We also have several consultants, and we do a good deal of research. In short, a lot of monitoring and work.

How many walnuts do you produce?

We have some 21,000 trees at Manjimup and a further 1,800 at Nannup. Our harvest last year was some 135 tonnes of walnuts comprising 83 tonnes of conventional and 53 tonnes of organic. The trees are far enough advanced for us to be confident we will have at least that tonnage in 2023.

When is your peak harvest?

The harvest varies as the seasons vary; however, in 2022 harvest ran from mid-April to mid-May. This year is running a couple of weeks behind due to an unusually mild spring; however, the nut size is our largest ever. Such is nature.

Can you tell me a bit more about how the processing of walnuts works?

We have a range of orchard equipment for harvest including tree shakers, sweepers, and harvesters. These deliver the nuts to our production line, where they go through another series of machinery to remove rocks, sticks, husks, and blighted nuts. The nuts are then conveyed to a series of dryers, then into a sizer, and from there either directly to the cracking room or to our refrigerated storage. The final part of the process is the packing room, where the nuts are packaged for distribution. All along the way aspirators, a colour sorter, and human inspection are employed.

Your products are known for being organic, how do you ensure this?

Our products are certified organic by ACO, and to pass muster there is a rigorous recording treatment required, declarations and audit. There is no doubt it is harder to grow walnuts organically—one of the major threats to walnuts is walnut blight (an airborne pathogen that attacks the fruit and thence the nut), and the standard conventional treatment, involving copper and mancozeb, is not available to the organic orchard, nor is urea. It is significantly more expensive to provide organic walnuts with the nutrients they require. 

How much of an impact on the quality of your produce does them being organic have?

I don’t think there is any difference in the quality of the product. It’s just that growing walnuts organically requires different husbandry due to a limitation on some inputs. We also farm naturally where possible by returning the walnut shells and needles from our shelter belt Casaurina trees (for its silicon) to the orchard floor.

Who typically buys your produce?

We supply some West Australian bakeries, but we believe our products, and particularly the chef’s pieces, are very suitable for baking not just bread but a range of baking delights. Next year we intend on adding walnut oil and meal (both conventional and organic) to our range.