Crop Nutrition and Climate Variability

In this episode of Tramlines, we’re joined by Thomas Perrott, Crop Input Specialist with Agrii, and Scott Garnett, R&D Agronomist for ICL Fertilisers.

Our focus today is on crop nutrition, specifically how to optimise it in the face of unpredictable weather patterns. 

We’ll also explore whether polysulphate can bring real agronomic benefits to cereals and oilseed rape, while meeting both environmental and economic goals.  

Addressing Crop Stress and Nutrient Deficiencies

What are we currently seeing in the crops from a nutritional standpoint? What are the main concerns?

Scott Garnett: One of the key concerns right now is crop stress. We’ve had a lot of rainfall, and as a result, many nutrients have moved away from the root zone.

Out in the field, I’m noticing deficiencies, particularly sulphur, which is putting crops under significant pressure. They need assistance to recover and hopefully produce good yields later in the season. 

What impact does that have on yield expectations?

Thomas Perrott:  It’s critical to keep nutrient balance in check. Think of it like the old *Liebig’s Barrel* – if one nutrient is deficient, it limits yield potential. Using polysulphate early in the season can help as it offers more than just sulphur—it provides a balanced nutrition package that supports crop health throughout the season.

What Is Polysulphate?

For those who might not be familiar, can you explain what polysulphate is and how it’s mined?

Scott Garnett: Polysulphate is a natural mineral we mine from deposits formed over 250 million years ago. It’s a single crystal that contains potassium, magnesium, calcium, and sulphur, releasing these nutrients gradually over time. This slow-release nature makes it particularly beneficial for crops, as it continues to supply nutrients even weeks after application.

Agronomic Benefits of Polysulphate

What are the specific agronomic benefits of polysulphate, particularly for root development and overall plant health?

Scott Garnett: Polysulphate offers more than just sulphur. The inclusion of potassium, magnesium, and calcium is essential for root establishment and development.

When crops have a stronger root system, they can better capture the nutrients applied to the field. This is especially important when crops are under stress, as it helps maximise nutrient use efficiency.

Environmental and Economic Advantages

Polysulphate also has some impressive environmental credentials. Can you tell us more about that?

Scott Garnett: Absolutely. We’ve recently announced that the carbon footprint of polysulphate has been reduced by 90%, thanks to our shift to renewable energy sources like wind and solar at our mining site.

This makes polysulphate one of the most eco-friendly fertilisers on the market today, with a footprint as low as 0.0029 kg CO₂ per kilogram of product.

Trial Results and Yield Improvements

Agrii has run trials on winter cereals using polysulphate. What kind of results have you seen?

Thomas Perrott:  We’ve seen consistent yield increases in the range of 350 kg per hectare in our winter cereal trials. The key to success is applying polysulphate early—either in the autumn or spring—so crops get the nutrients they need when they’re most vulnerable.

This improves root strength and overall plant resilience, setting them up for a better spring and reducing the risk of poor yield due to unpredictable weather.

Misconceptions About Polysulphate

There’s a misconception that polysulphate needs to be applied early because it takes too long to break down. Is that true?

 Thomas Perrott: Not exactly. While polysulphate does break down slowly, that’s actually one of its strengths.

It releases nutrients gradually, ensuring that plants have access to them over a longer period. Just because you can see it on the ground doesn’t mean it’s not working—it begins releasing nutrients as soon as it’s applied, particularly when it absorbs moisture.

Advanced Fertiliser Technology: Drill Plus

You’ve developed a product called Drill Plus. Can you explain how it works?

Scott Garnett: Drill Plus combines polysulphate with a controlled-release nitrogen technology called AquaCoat. 

The nitrogen is encapsulated in a polymer, which regulates its release based on temperature. As soil temperatures rise, the polymer expands and cracks, allowing water to enter and dissolve the fertiliser.

This gradual release of nutrients ensures they’re available when crops need them, even during cooler winter months.

Why Growers Should Consider Drill Plus

Why should growers consider using Drill Plus in their crop management strategies?

Thomas Perrott:  Drill Plus offers a reliable way to provide crops with balanced nutrition at the most critical growth stages.

The slow-release nitrogen won’t leach away in heavy rains, protecting the farmer’s investment and ensuring that nutrients are available when soil temperatures warm up. 

It’s a great solution for protecting crops from nutrient loss during unpredictable weather patterns.

Top Tips for Farmers

Can you both share some top tips for farmers listening today?

Scott Garnett:  My advice is to really understand your soil. Knowing what nutrients are available can help improve nutrient use efficiency. Also, consider applying polysulphate or Drill Plus in the autumn to capture more nitrogen over the winter period.

Thomas Perrott:  From a risk management perspective, polysulphate is a great investment. It’s an affordable product that provides long-term benefits, and by using it strategically, farmers can reduce their exposure to market risks and safeguard their crops against unpredictable weather.

Thank you, Tom and Scott, for sharing your expertise on crop nutrition and how products like polysulphate and Drill Plus can help farmers manage risk and improve yields.

To find about more about Agrii fertiliser services, visit agrii.co.uk/our-services/fertiliser