With the summer season being a busy time for farmers and growers keen to get the fert’ on, there’s often a tendency to focus on getting the job done, rather than think too much about what’s in the product or how it’s being applied, says the Fertiliser Quality Council.
The organisation, which overseas Fertmark and Spreadmark, the industry schemes which respectively set benchmarks for fertiliser quality and application, says where a single nutrient fertiliser is being applied this isn’t too much of an issue.

But where multiple nutrients are being applied, farmers and growers need to know whether the product is a single compound fertiliser or a blend of products so they can then understand how it will spread and so manage their own expectations.
A compound fertiliser, for example, is made up of several nutrients combined into a single, evenly sized granule. These granules are manufactured as uniformly as possible in terms of shape, size and weight. When distributed, compound granules tend to flow freely and evenly, promoting even growth.
By comparison, a fertiliser blend may feature less uniform granules with particles varying in size, shape and weight. There’s a risk that particles can segregate resulting in some not being thrown as far as others leading to uneven distribution and a risk of striping.
Anders Crofoot, FQC Chairman, says it’s important for farmers and growers to know the characteristics of the fertiliser they have ordered so that they understand the distribution outcomes.
“If accurate and even spread is critical to the growth of the crop, a quality compound will achieve those results. If accuracy is less important, a more cost-effective blend might be best.
“Whichever farmers and growers choose, it is critical that they talk to their spreader operator and discuss product and application details. Spreader operators are highly knowledgeable about fertiliser products and will calibrate their vehicles to best suit the fertiliser type. Good communication will ensure that there are no false expectations around how a product will spread.
Mr Crofoot adds that farmers and growers should always ensure they are using a Fertmark approved fertiliser and a Spreadmark accredited spreader operator. “Fertmark guarantees that what’s in the bag is true to label and a Spreadmark accreditation means that highly trained operators can guarantee that distribution is as accurate and even as possible, as well as to the farmer’s best agronomical and economic advantage.”
To ensure a fertiliser is Fertmark verified, farmers and growers are encouraged to look out for the Fertmark logo as well as ask the question of their manufacturer or supplier. More information about Fertmark and engaging a Spreadmark certified operator is available at www.fqc.co.nz, where the latest list of Spreadmark Registered Companies can be downloaded.