An Australian farmer who has found green ways to grow crops in extreme heat and droughts has given advice to his Norfolk counterparts.

Grant Sims spoke at a virtual online meeting hosted by the Royal Norfolk Agricultural Association and its Yield (Young, Innovative, Enterprising, Learning and Developing) rural business network.

With extreme weather becoming more common in East Anglia, he explained how he has optimised the health and resilience of his soils to cope with the rigours of an Australian summer.

He farms 8,500 acres in Victoria, including a 300-strong herd of Angus cattle.

He also runs Down Under Covers, a business which sells seasonal multi-species cover crop mixes to farmers across Australia.

And keeping soil covered with plants between commercial crops is one of the key "guiding principles" on his farm, which can receive less than 200mm of rain during the growing season, and often sees 40-degree heat and heavy storms in summer.

He said "cover is king", helping insulate the soil and improve its biology, while a variety of root depths breaks up compaction and increase the water-holding capacity.

"One thing we are really focused on in our soil health is to improve that infiltration and water-holding capacity," he said.

"Most of the time we look at the area we are farming two-dimensionally, but really we are farming a three-dimensional plane.

"So if we can increase the rooting depth and the water-holding capacity, we can make use of this out-of-season rainfall, store it, or grow something over the summer which has traditionally not been done - and that is where we implement our cover crops to get the diversity in."

Mr Sims said 2015 was an example of this approach working.

One field received just 159mm of rain in the growing season, and four days of 40-degree temperatures during the grain-fill period - but he was able to harvest 1.9 tonnes of grain while other growers were "cutting crops for hay because they had all fallen over with the heat".

Mr Sims, a sixth generation farmer, decided to stop using synthetic fertilisers, fungicides and insecticides when he returned to the family farm in 2008.

The farm now makes its own biological liquid fertilisers.

As well as year-round soil cover, Mr Sims' other "guiding principals" include to eliminate or minimise tillage, maximise diversity in rotations, minimise chemicals and synthetic inputs, and integrate livestock into the rotation.