Liming increases wheat yields and profits

Long term average

Trials have shown that Aglime increases wheat yields up to 17% in the central and northern wheatbelt.  For many years now, Aglime of Australia has measured the yields and topsoil pH of 935 plots from 75 trials at 25 sites where wheat was sown.

Effect of soil pH on yield

The trial results show that as topsoil pH increases after liming, wheat yields increase on average by 8.5% per pH unit increase.

Location and yield response

Yield increases varied from site to site in our long-term research programme.  The highest average increase was 17% for 1 pH unit increase following liming and was achieved over 5 wheat crops between 1985 and 1993 on productive tammar country (loamy sand over gravel) north of Goomalling.

Although no reduction in wheat yields was measured from liming, it is evident that sites low in zinc and/or manganese show lower yield increases from liming.

Long term yield responses

Wheat yield responses tend to increase over time with the best results 3 to 4 years following liming. In the long-term Aglime trials we have been able to demonstrate that aglime lasts for many years.

How Aglime increases yield:

Aglime can increase wheat yield by:

Increasing nitrogen

Nitrogen is increased by improved nodulation of legumes and N fixing by free living bacteria.

Increasing the availability of nutrients

Nutrients such as phosphate are more available at higher pH.

Increasing soil moisture levels

Moisture levels increase through improved soil structure and soil wetting.

Increasing microbe activity

The number of microbes and microbe activity increase, resulting in faster breakdown of organic matter to release nutrients, especially nitrogen.

Reducing aluminium toxicity

Aluminium levels are reduced resulting in better root growth.

It is most likely that a combination of these improvements lead to yield increases at any site.

Take action to increase your yield response from Aglime

Tissue sample and apply trace elements (particularly zinc and manganese) and other nutrients where marginal or deficient.  Reduce take-all through grass control and/or acidifying fertilizers.


Aglime of Australia thanks the following organisations and people for financial support and assistance in its field trial program: Grains Research and Development Corporation, CSBP, Summit Fertilisers, Robert Jenzen of Cunderdin, David Antonio of Northam, Mark Brockhurst of Goomalling, Charles Chitty of Konnongorring, Geoff and Lindsay White of Konnongorring, Ian Leeson of Goomalling, Barry Morrell of Ejanding, Bill Dickson of Wyalkatchem, Jim Shepherd of Kwolyin, Gilbert Ackland of Wongan Hills, Neil Scotney of Kondut, Graeme Dodd of Kalannie, Ian Bowman of Carnamah, Peter Smith of Carnamah, Gordon Pearse of Mingenew and Trevor Ryan of Yorkrakine.