A Western Australian grain grower says he's changing the way he farms to combat the effects of a changing climate.

Trevor Syme farms 3800 hectares between Bolgart and Goomalling 130 kilometres north-east of Perth, cropping wheat, barley, oats canola and lupins.

He’s one of three finalists in grain grower category of the .

Trevor has pin-pointed non-wetting soils as his biggest yield constraint so he's set up a series of trials on his property to look at the most cost effective way to improve it.

“This clay rate trial is looking at the economic value of clay spreading and incorporation.

“When finances are available we do as much claying as we can.”

The trial covers three different clay rates - zero tonnes to the hectare, 260 and 520.

“So far so good, we’re getting some big yield responses from it but there’s an expense to go with it, for example clay spreading and spading can be up around $800 to $900 a hectare,” Trevor said.

“We have shown we can recoup that in two years so it’s definitely worth doing.”

The winners of the will be announced in Melbourne on Thursday 12th September.