Solid fertilisers have been the foundation of crop nutrition for centuries. Yara's own roots, which can be traced back to 1843, lie in phosphate fertiliser – and since the advent of the Haber-Bosch process for producing ammonia – NPK.

However, as weather volatility continues to challenge farming operations, an increasing number of growers are adopting a hybrid approach to crop nutrition. With solid NPK fertilisers used for baseline nutrition in conjunction with liquid applications for precision timing and accuracy. 

This hybrid approach maximises efficiency, maintains flexibility and offers practical solutions to the unpredictable conditions that have characterised recent growing seasons.

Fine tuning your approach to match the season's demands 

James Willis, Yara's Area Manager for Norfolk, told us "Solid fertilisers still provide the foundation for most crop nutrition programmes. Spring applications of NPK fertilisers have consistently outperformed the traditional autumn applications of PK fertilisers in independent trials, with yield responses averaging 0.3 tonnes per hectare. By applying these readily available phosphorus and potassium in the spring, you're matching the application with the peak crop demand and not limiting the crop's momentum," he explained.

These benefits extend beyond simple yield gains. Spring applications prove particularly valuable following cold and wet winters, when soil nutrient availability is lower and root systems may be compromised due to anaerobic conditions.

But liquid fertilisers have come a long way since slurry and can also offer distinct advantages in challenging conditions. Applications are less affected by weather compared to solid fertilisers, providing more available working days. Wind and rain don't stop liquid applications and may even help prevent leaf scorch by improving fertiliser run-off from leaves to soil.

Conversely, during long dry spells like this year, liquid fertilisers don't need to dissolve into the soil solution to become available, offering immediate accessibility to crop roots. "Liquid nutrition is more readily available than solid," Roger confirmed. "So in a dry year, there is a little bit of an advantage in that the plant roots can take it up pretty much readily and you don't have nutrients lying around in the soil, undissolved and not being utilised."

Whilst research data spanning many years has been analysed to understand the pros and cons of the different types of delivery, sometimes simple practicalities dictate the decision. 

Roger Bacon from Yara's Crop Nutrition Services team explained "Two years ago we had wet springs, and with a big sprayer full of liquid fertiliser, it could be quite difficult to travel," he said. "In very wet conditions, some growers may find spreading solid fertiliser easier thanks to a lighter machine. Equally, if there's an NPK approach, there's a finite amount of nutrient that can be dissolved in a cubic metre of liquid, so it could also work out more practical to apply that as a solid for the first application."

Precision agriculture benefits

The move towards more sophisticated farming practices has further strengthened the case for hybrid system. Liquid fertilisers integrate seamlessly, with advanced nozzle and dribble bars and precision agriculture technologies offering GPS control and section control capabilities that enable far more accurate application.

"Rather than having to spread up to 40 metres, you can apply liquids in section widths across the field," Roger explained. "You get more uniform application with liquids. There's no headland effect, less wastage, and it is far more efficient."

The precision advantage addresses in-field fertility variations more effectively than traditional broadcasting methods, allowing growers to target specific areas requiring attention.

A combination of operational flexibility and economic benefits

The hybrid approach also provides practical solutions to labour and machinery management challenges. During tight weather windows, solid and liquid application can run simultaneously, with the spreader handling baseline nutrition whilst the sprayer remains available for its primary task of crop protection applications.

James Willis emphasised the strategic flexibility: "If it's particularly tight weather windows, you may want to look to have both machines running at the same time. Or if there's volatility in the market, liquid may be more attractive than solid or vice versa. It just gives more options."

For farms operating at maximum sprayer capacity, the ability to distribute workload between different application methods reduces pressure during critical periods and ensures timely nutrient delivery.

Planning ahead for success

Growers considering adopting a hybrid system need to plan ahead, particularly if transitioning from an exclusively solid fertiliser programme. The switch to incorporating liquid fertilisers requires investment in storage tanks, preparation of suitable storage areas, and ensuring sprayers are equipped with appropriate dribble bars or nozzles.

"The switch to liquid can't be done overnight," James advised. "If it's something you're thinking about for this season, I would recommend having those conversations now and reaching a decision ahead of spring when it's going to be applied."

Supply chain challenges in recent years have reinforced the importance of early decision-making and advance ordering. Having product on farm before the critical spring period removes uncertainty and ensures growers can respond immediately when crops begin rapid growth.

Roger Bacon summarised the forward planning requirements: "It's important just to plan ahead, to make sure that we can advise you on tank installations and get tanks in place on time, and just to make sure that everything's going to work seamlessly from a delivery point of view and the logistics on farm."

Tailoring the approach

As climate uncertainty continues, the flexibility offered by hybrid fertiliser systems provides another valuable tool for growers navigating unpredictable conditions whilst maintaining crop nutrition standards. 

The key message from James and Roger is that the correct approach will differ for each farming business. But as the only manufacturer and supplier of both solid and liquid fertilisers, Yara is positioned to provide impartial advice on the most suitable strategy for individual operations. "If you are thinking of making changes to your system, reach out to your local area manager to assess your options." James Willis concluded.