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AeroLime™ Project Launch (February 2019) After an extensive product development phase Graymont’s new AeroLime™ product is ready for takeoff.
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Case Studies - AeroLime™

Turning Pasture into Profit

Five years after the conclusion of an intensive lime programme Chris Adams of Kopaki in the King Country region is still counting his blessings.

The whole project started in 2010 after Chris had read an article about the benefits to pasture and stock when pH levels were increased up into the 6 plus range. At the time the levels on his 400 ha property were around 5.7.

“In the beginning it was very much ‘toe in the water’ stuff” said Chris.

“Also, although we were focusing on our bulls, most of the data available at that time only referenced lamb and ewe responses to lime trials”.

Chris started off spreading an 80ha section of the farm at a low rate 500kg/ha. As he recollects, part of the block was ground-spread and the other by plane.

“Then in the 2nd year we decided to get serious and go the whole hog”.

Going the whole hog saw Chris aerial spreading an additional 200 ha at a rate of 4 tonnes/ha. Then in the following year he covered the remainder of the property at the same 4-tonne/ha rate. Throughout the 3-year period he also kept an un-limed control block on the property.

“As I recall one of the early changes that we noticed was in the colour of the pasture which was greener than the control block. We also started to notice that the pasture in the limed blocks has been grazed much more evenly – right out to the fence lines - and an increase in clover content”. 

Soil Scientist Paddy Shannon of Shannon Agricultural Consulting commented on the stock preference for limed over un-limed pasture. 

“The grazing responses observed on Chris’s property are consistent with those from a number of other studies and suggest that stock find limed pasture to be more palatable than the un-limed alternative. It also suggests that stock in these limed blocks are increasing their dry matter consumption and this delivers obvious benefits for farmers”.

The third and final year of the trial coincided with the indication of a dry patch on the horizon and pH levels reaching 6.2. Chris made the decision to send his bulls off earlier than he usually would, and at this time, perhaps the most significant benefit of the liming programme, became apparent. 

As shown in the following figures, the total killed-out kg/ha of stock from the limed 2 years trial block was almost double that of the un-limed control block.


Limed 2 years
Stocking: 2.2 bulls/ha. All were drafted.
Killed out at 285kg/head to give 627kg/ha.

Limed 1 year
Stocking: 2.0 bulls/ha. 90% were drafted.
Killed out at 270kg/head to give 486kg/ha.

Un-limed control area
Stocking: 2.2 bulls/ha. 60% were drafted.
Killed out at 265kg/head to give 318kg/ha. 

Five years later, with his soil pH still in the optimum 6.2 range, Chris is still getting similar growth performance from his bulls. He is also now enjoying strong and fast weight gains from his lambs, as well as the ability to consistently draft stock off early and avoid drought related problems. Pasture density and clover content are excellent and stock health has greatly improved.

“Our liming programme continues to return real dividends for our business”, said Chris. “We now soil test on a regular basis to monitor our soil pH”.

For further information Freephone 0800 245 463

Increasing pasture production and stock performance

With NZ Beef + Lamb predicting 2018 - 2019  lamb and beef exports to both break
$3 billion for the second time1 the launch of AeroLime™ is timely for hill country farmers.

Research carried out over a 3- year period in the Te Kuiti district has shown that low rate aerial liming can deliver significant benefits for hill country properties2. This research, which investigated the production responses to low rate applications of lime at 1.25t/ha, was published in 1981 and highlighted a number of important factors.

Number one was that lime – even at the low application of 1.25t/ha helped increase pasture production. 

The main response to the lime appeared 15 months after the initial application, increased over time, and was still present 3 years after application. Other pasture and soil related responses recorded were improved legume content, decreased pasture litter and an increase in earth worm numbers.

The trial involved Romney and Border Leichester-Romney ewes, rotationally grazed at 14 ewes/ha, except during lambing, when they were set stocked. During the 3-year period the following stock performance related data was recorded.


Fleece weights of both ewes and lambs showed responses to lime with an additional 0.5 to 0.6kg of greasy wool per ewe and up to 0.13kg per lamb being obtained during 1978 and 1979. This effect was attributed to the better overall nutritional plane of the limed pasture. 


“Limed” Lamb weights at weaning were 3kg better and during the last year of the trial 55% of lime treated lambs were ready for slaughter on 19 Feb, as against 38% of the un-limed. Ewe live weights in the limed sector were also around 5kg higher. Of interest – during the 2nd year of the Hill Country study a dry autumn resulted in rainfall being 40% below normal. Despite this, the increase in pasture availability allowed ewe weights to be maintained. According to soil scientist Paddy Shannon, this is consistent with other observations suggesting lime has a strong positive effect on soils and pasture under drought conditions. 

“This is because limed soils retain water better and wet up faster than un-limed soils. Lime is therefore an important weapon in helping to reduce the long-term effects of drought.”

AeroLime is a minimum 92% calcium carbonate product manufactured through a specific crushing, screening and storage process. Extensive testing ensures that the product purity, particle size, moisture content and other factors consistently meet Graymont’s exacting specifications. These strict manufacturing and storage processes maximize product flowability in accordance with CAA guideline safety recommendations3 while still allowing AeroLime to achieve agronomic performance expectations. 

Graymont is committed to manufacturing AeroLime to a high standard. Farmers should contact their usual approved transporters and contractors to order.

For further information Freephone 0800 245 463 

1 2018-19 lamb and beef exports forecast to both break $3 billion for the second time (2018, September 14), NZ Beef + Lamb. Retrieved from

2 O‘Connor, M.B.: Foskett, H.R.; Smith, A. 1981. The effect of low rate of lime on North Island hill country pasture and animal production and the economics of use. Proceedings of NZ Society of Animal Production 41:82-87. 

3 Safety Guideline – Farm Airstrips and Associated Fertiliser Cartage, Storage and Application. Jointly published by the Civil Aviation Authority and Department of Labour (2005).