Watch: ‘Real danger’ of fertiliser being substituted for concentrates

Since the Middle East conflict escalated in February, fertiliser prices have surged, posing a significant risk for farmers to substitute fertiliser with concentrates. This trend was also evident in 2022 when extremely high fertiliser prices followed the Russian invasion of Ukraine, leading many farms to reduce fertiliser usage. However, many of these farms were not prepared for such a shift and suffered losses in herbage production. As a result, they ended up spending more money on fertiliser through concentrate supplementation than they would have under normal circumstances.

Four years later, Dr. Joe Patton, the head of dairy knowledge transfer at Teagasc, warns that farms are once again in "real danger" of facing the same situation. Patton emphasises that the high cost of fertiliser may tempt farmers to reduce their nitrogen fertiliser application, potentially leading to a reliance on concentrates. He explains that the response to fertiliser can be as much as 20kg/dry matter (DM) growth per kg of nitrogen (N) spread, particularly as the days grow longer and the weather improves.

The Teagasc representative points out that economically, 1kg of N can more than feed a cow each day. Patton further argues that while fertiliser prices may seem expensive in the short term, when considering the growth response per kilogram of N, it ultimately proves to be a more economical option. "It makes far more sense to spread the fertiliser and grow the grass than to spend that additional money on concentrates," he states.

Patton also highlights that getting fertiliser onto silage swards could be an issue this year. He cautions against saving on fertiliser in the short term, as it could result in a "false economy." Farmers might end up buying silage the following year, which could be more expensive than the initial investment in fertiliser.

In 2025, silage harvesting was particularly successful, allowing many farms to build up reserves. These reserves proved beneficial during challenging spring conditions this year. However, as these reserves dwindle, the need for careful fertiliser management becomes even more critical. Farmers must balance the cost of fertiliser with the long-term benefits of healthy pasture growth to avoid the pitfalls of relying on costly concentrate supplementation.

In conclusion, the risks associated with substituting fertiliser for concentrates cannot be underestimated. While the high cost of fertiliser may seem daunting, the economic and agricultural advantages of maintaining proper fertiliser application are significant. Farmers must carefully consider their options and prioritise sustainable pasture management to avoid the potential drawbacks of a concentrate-heavy approach. As Dr. Joe Patton's warnings underscore, the stakes are high, and the consequences of underestimating the importance of fertiliser could be costly in the long run.