Shedding Light on Granule Distribution and P Rates

Cropping fertilizers vary significantly in their phosphorus (P) content. Summit’s AllRich for example contains 8.7% P, compared to 22.8% for MAP. It follows that different fertilizers need to be applied at different rates in order to achieve the same desired target P rate. Granule output from seeding machinery will also differ and the space between granules (distribution) will vary between product.

This has clear implications from a logistical standpoint. Using low analysis products results in greater loading, freight and storage requirements, plus greater downtime from more frequent fills at seeding, compared to higher analysis products.

Relative distribution of compound granules and seed along rows at 10-inch tine spacing.

What is less clear however is how granule distribution can impact P availability to the growing seedling. To investigate this, Summit’s Field Research team collected data on the number of granules in a unit mass of 3 fertilizers – AllRich, MAP and MAPSZC. Calculations and models were then made to determine granule distribution patterns.

Key conclusions from this study:

  • High analysis products contain 50% (MAPSZC) and 90% (MAP) more P per granule than AllRich.
  • At reasonable seed rates (using Scepter Wheat) with appropriate target P rates, each seed will have access to P from more than one fertilizer granule regardless of the product (AllRich, MAP or MAPSZC) used.

For further information, see our technote.



New & Improved SummitConnect Portal

At Summit, we are committed to ease of doing business and freeing up more time for our customers so they can spend it on what’s important to them. This is why we’re delighted to announce that our new and improved SummitConnect online customer portal is now available.

The latest version of SummitConnect links customers to our inSITE platform, so they can view and download their entire soil and plant test history, including recommendation reports.

Another exciting feature that has been added are trend maps, which allows farmers to visualize how soil nutrients are tracking over time, across different depths and in different paddocks. Ultimately our aim is to provide our customers with the most accurate data, in the most accessible way, enabling them to make better decisions with regard to their fertilizer inputs for next season and beyond.

A SummitConnect trend map showing pH results at 0-10cm depth across all years and paddocks.

We’ve also developed a new user-friendly interface, allowing clients to easily view:

  • Orders - See details of all of your orders with Summit, including collection month and payment terms.
  • Collections - View individual fertilizer collections and download loading and weight dockets.
  • Transactions - Review your payments, credit limit, monthly statements and download your tax invoices. 

The new SummitConnect dashboard 

With the new SummitConnect portal everything you need is in one place, which makes it easier than ever to manage your business with Summit. In addition, providing your accountant or consultant with access to your SummitConnect can save you time when it comes to the end of the financial year.

If you’d like to learn more about how our new SummitConnect customer portal could benefit you, get in touch with your local Area Manager.

To register for SummitConnect, email; or phone; 9439 8999.

Working together for Agriculture

Summit Collaboration

Each year Summit conducts more than 30 field trials across the farming areas of Western Australia.

In 2018 we have been part of an ongoing research project, funded by the GRDC, looking at the major nutrients, Nitrogen, Phosphorus and Potassium.

The project is titled “Increasing profit from N, P and K fertiliser inputs into the evolving cropping sequences in the Western Regionand aims to provide clarity to critical soil analysis values and recommendations for a number of crops.


Summit’s role in this project is to provide Phosphorus trials, and some potassium trials as well.

This is a large project with Summit’s role in 2018 being 6 trials located at


  • Northern Ag Group – Binnu
  • Mingenew
  • Williams
  • Merredin
  • Yealering


  • East Ballidu

The results of these trials will add to the pool of data that Summit has amassed from our over 25 years of field research in Western Australia.

New Quicker Liquid Loadout at Kwinana

Summit Fertilizers has installed a new liquid fertilizer loadout facility at Kwinana.

Read more