Tillage radish performs well at Buckleboo

Leigh and Laura Fitzgerald have put in a "paddock-scale trial" to see if sowing tillage radish, alongside their usual vetch cover crop, could help boost yields in future years.

Mr Fitzgerald said he had heard positive reports from other regions, but wanted to see how tillage radish could perform in their climate.

"It was initially around trying to find a way to deal with hard setting soils and plough pans 90 millimetres to 100mm down in heavy clay soils," he said.

They had tried deep ripping but experienced negative effects, so decided to trial the theory that the roots of the radish could help ameliorate the soil.

He said it was also beneficial that tillage radishes were "quite good scavengers of nutrients", and could access nutrients deeper in the soil that might be released when the crop is sprayed out this month.

The 200-hectare paddock was sowed in early April, after three seasons of wheat, into good moisture at a rate of 2 kilograms/ha for the radishes and 25kg/ha for vetch.

Mr Fitzgerald said the sensitivities of the radish meant they could not use any herbicides and they also did not apply fertiliser.

"We're trying to improve soil health by putting in more species and also get good microbial activity," he said.

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He said the combination of the crop ensured good biomass and soil cover.

Even before harvest, he has learnt lessons for next year, when he expects to repeat the experiment.

"Next year I will likely swap back to 1kg/ha seeding rate - the density of the radishes far outweighs the vetch," he said. "I may also reassess fertiliser application, based on soil sampling."

He said even though the vetch had been dominated, the nodulation of the vetch roots near the tubers were still quite good. But he said one important realisation was seeing it successfully grow in a drier area, with a growing season falls of 200mm.

"It's a new field within Australia, particularly in this region so it's exciting from our point of view to know it can survive and grow quite happily," he said.

"It had been quite dry through May and June, but it didn't seem to fuss, it kept growing happily."

Mr Fitzgerald said in areas near water, such as troughs, the radish seemed to grow particularly well.

He left a 10ha strip of just vetch when sowing so a comparison of the soil health impacts could be made.

"We will see next year if that makes a difference," he said.

They have two properties, with about 3270ha of arable land, and work on a rotation of 70 per cent cropping and 30pc legume-based break crop.

"Some crops may not pay you back that year but because they do something magical to the soil, they pay off in later years," he said.

While his initial plan was based on improving soil health, Mr Fitzgerald says he has changed his "mindset" about the potential benefits of incorporating tillage radish.

He sold off the last of his livestock earlier this year but has been agisting a neighbour's sheep on the tillage radish and vetch combination and said the results had been impressive.

"It turns out the feed value there is very substantial - good quality feed and the ewes and lambs are loving it," he said.

"I didn't even think about the feed side but it has changed my mindset - I could see a lot of interest in the feed value."

So far 330 ewes with lambs at-foot have been feeding on the crop with an extra 400 ewes and LAF expected.

The Fitzgeralds are no strangers to trying new ideas, with Mr Fitzgerald having previously trialled summer crops, including dryland cotton, with mixed success.

He said it was vital to trial new ideas to see how they might work on their farm.

"Unless you get out, do it yourself and see for yourself, none of that information actually sticks," he said.

"Doing our trial and seeing it from the start through to the finish and seeing whatever improvements or negative aspects are associated with the trial, it sticks in the memory banks."