In the summer of 2009/10, a severe heatwave hit South-East Queensland, shutting down the Ghost Gully Produce farm in Gatton for five weeks. Farm losses are, of course, costly in terms of lost product and production, and potential lost customers. Temperatures of up to 45°C were being routinely reached. Overhead sprays were used to cool the systems, but were blown over the systems by westerly winds.

We were desperate to cool the systems, but the best cooling towers were only capable of reducing temperatures by 4–6°C. Their effectiveness, pricing and running costs made us wonder if there could be a better way.

Gatton is not only prone to extreme summer temperatures, but also to sub-zero winter temperatures. What was needed was a solution to thermal dormancy (and worse!) in summer, and growth shut down in winter.

I stumbled across heat pumps with underground piped heating used in European homes to maintain an even temperature through summer and winter—could that work here? I tried to research ground temperatures, but data was difficult to come by. A customer knew of a farmer who had trialled a similar installation, but only achieved limited success. The idea was clearly not new, but if we could make it work well, it would be a solution for summer and winter, with reduced overheads compared to other heating and cooling methods. Still, we were flying into this blind.

Click through to view a Practical Hydroponics article explaining the application of farm automation and ozone at Ghost Gully Produce, Gatton.

Ghost Gully Produce

The following are a selection of recipes for farms choosing not to use pesticides and fungicides. Cyber-Hydroponics is currently developing a vinegar-based herbicide, and we’ll let you know when it’s in production.