Nut borer on Macadamia tree last year. Lost every nut. Could you advise what to spray and when please.

Unfortunately - as far as we aware - there are no home garden approved products for the control of Macadamia Nut borers.

To reduce and prevent borer infestation, we recommend improving the health of the plant and try to prune the stems/branches that are infested where possible. Yates Dynamic Lifter Soil Improver and Plant Fertiliser is an excellent fertiliser for natives, including macadamias, and will help with plant growth and health.

Pick up any fallen nuts, place into a plastic bag, then put into the rubbish bin. This will help to reduce the amount of pests in the environment.