The Importance of Crop Rotation

Author Growing Solutions
Branding Ag Excellence
Credits SA No-Till Farmers Association
Video Transcript

Greg Butler of the South Australian No-Till Farmers Association talks to us about the benefits of crop rotation. One of the biggest problems in trying to grow a mono-crop is disease. The problem is if you go and grow the same crop again the following year you’ve got those same pests and diseases hanging around ready to pounce. And so what rotation can do both in terms of airborne disease a soil born disease is give the soil what they call a break, okay? And so what we’re able to do is minimize the risks that are associated with a disease of a specific crop.

Extra Nitrogen Means Savings on Fertilizer

The other thing about rotation is bringing in in particular things like legumes because they can bring in extra nitrogen from the air, and then they can be a source of nitrogen rather than using chemical fertilizer, although chemical fertilizer will still be required in some circumstances as a supplement still being able to get that rotational benefit can have as quite as significant cost benefit.

Personal Experiences with Crop Rotation

Allen Buckley, of Glenray Holdings, Waikerie, South Australia shares his personal experiences with crop rotation. in the last couple of years, we’ve been playing around with sowing wheat after barley, in other words, just going two wheats, then barley, then wheat again, then going back to oats. The wheat crop after barley tends to be quite a good wheat crop.

We try and sow 50% of our property to wheat a year and then 25% to barley and oats and 25% canola and cereal rye to try and make a balance. What we found is The canola is the key to the rotation. It tends to give us a good disease break which then gives us the next three crops after that high yielding with the paddocks where we haven’t had canola where we’re just sown wheat without a canola break crop.

There’s a little bit of work to do on the rotation and I don’t think it ever stops, it’s just keep on going and trying different things. But certainly breaking the three wheats up and putting the barley in the middle appears to have some benefits to gain in terms of yield without actually costing anything in terms their chemical applications, etc.

Since 2009, Rick Llewellyn and Therese McBeath of the CSRO have been conducting trials on break crops in the Mallee region What we What we really aim to do is understand where the break effects are coming from. Is it biology? Is it nitrogen, is it water? Where are the big break effects coming from in terms of benefitting from the wheat crop that follows and we’re seeing big break effects out here and it’s a matter of explaining what’s driving those so that farmers can understand what might work and when.

Crop Productivity Benefits

In every season we have evaluated the productivity of a range of break options like canola, lupins, peas, rye and we’ve also looked at the effect of those breaks on subsequent wheat crops and we’ve looked at the effects on the subsequent wheat crops not just from a the perspective of yield and economics, we’ve also considered what some of the chemical and biological factors might be that causing this break effect where we get up to one ton extra weight yield in a season after a break.

We did see a second year break effect so two years after the break we were seeing around 10% wheat yield benefits. I think we will need be quite strategic about when we use those breaks rather than having a fixed rotation, we need to think about the best Agronomy for those break crops and the best season types for those break crops and fit them in when the opportunity arises because we know of these benefits that we have associated with them.

Crop rotation is an important facet to conservation farming.

Local South Australian experts and farmers speak to us about the importance of crop rotation.

Leave a Comment

Back to top