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Tag archive: fertiliser

Looking closer at Colwell-K on heavy soils

Colwell potassium (K) is the go-to K test in many growing regions. Colwell-K measures extractable K and is used to estimate plant-available K.  But interpreting Colwell-K values gets tricky on heavier soils. This is partly because research on critical values has been dominated by Western Australian sandy soils. There is […]

Sowing time and conditions affect P requirements.

  The amount of residual phosphorus (P) a crop takes up is largely determined by soil moisture and soil temperature. These conditions can vary significantly across a typical three-month sowing period from April to June. This variation can impact the P fertiliser requirements of crops at sowing. Recent trials in […]

Correcting acidity with lime can induce Mn deficiency in lupins

Lupin growers are being encouraged to assess their crops for manganese (Mn) deficiency. This has re-emerged as a problem in recent seasons, causing split seed disorder. The GRDC’s Western Lupin GrowNotes says this can result in yield penalties of up to 70%. According to Jeremy Lemon from WA’s Department of […]

An updated Nitrogen Nutrition Index to check in-crop N

The Nitrogen Nutrition Index (NNI) is one way to help gauge in-season crop status. The NNI is the ratio of the amount of N in the crop to the critical N concentration (Nc) of the plant tops. By comparing crop N (from lab tests) to a dilution curve with Nc […]

The best of 2018

open ebook and Cover of ebook

GRDC’s Crop Nutrition Community of Practice continues to be an important extension initiative for industry, providing reliable information sourced from key research scientists across Australia.  Throughout 2018, we published 46 articles (that’s a lot!). So, we collected our most popular articles from this period – those that best reflect the […]

Register now: Australian Fertilizer Industry Conference 2019

“Register now for the 2019 Australian Fertilizer Industry Conference.”

Register now for the 2019 Australian Fertilizer Industry Conference. Early bird registration closes at midnight on July 26.  When: 4–6 September 2019. Where: RACV Royal Pines Resort, Gold Coast. With a diverse conference program, just some of the topics of interest include: Fertilizer application technology The potential for potassium fertilizer […]

WATCH: Is it time to re-think P critical levels in WA?

Applying phosphorus (P) to soils with seemingly adequate P stocks can boost yield. Trials in WA are showing crop response to P above critical levels. Critical levels indicate if a crop will respond to more of a certain nutrient. Above the critical level, there’s less than a 10% chance of […]

Keep K in soils to alleviate stress

At a recent GRDC Regional Cropping Solutions Network open forum at Morawa in Western Australia, Dr Richard Bell from Murdoch University spoke of the importance of potassium (K) for optimal plant growth and alleviating crop stress. Low soil K is common in the sand and duplex soils of WA cropping […]

Insights from N rich and poor strips

Tom Batters and his colleagues from AGRIvision Consultants, Swan Hill, Victoria have been using nitrogen-rich test strips (N-rich strips) informally for many years.  Last season they took a more formal approach and followed the test strip progress with photos and NDVI images. The strips are a real time, low-cost visual […]

Get better precision with grain tests

Grain nutrient testing is a quick and easy way to see what nutrients are leaving the farm with the grain. Incitec Pivot trials at the Darling Downs, western Downs and in northern New South Wales have looked at sorghum grain test results from the last three years of summer crops. […]

2018 in review- Crop nutrition implications for 2019

In November 2018, plant nutrition consultant Rob Norton presented growers and advisors with yet another insightful review of the 2018 cropping season, and how it may impact crop nutrition in 2019. Rob’s webinar focussed on the more strategic nutrient management decisions. These are longer-term objectives (3-5 years), planned at the […]

What is the phosphorus buffering index?

The Phosphorus Buffering Index (PBI) approximates a soil’s ability to ‘fix’ phosphorus (P). Soils with a high PBI quickly and tightly bind fertiliser P making it unavailable to plants. Low PBI soils can’t lock-up much P, leaving most applied P for plant uptake. Use PBI to improve interpretation of critical […]