Farmers are facing greater challenges than usual this year, driven by a rapid rise in input prices and increasing pressure to adhere to environmental guidelines – and all while trying to fulfil yield potential.

For Jonathan Telfer, laboratory manager at Yara, many of these challenges could be met by focusing on fundamentals – especially soil health.

“If there was ever a year to pay more attention to your soil, it’s this one,” said Jonathan. “Last year, at our lab in Pocklington, we processed 250,0000 samples from more than 60 countries. Our results database has 100m entries so, in short, we have a good knowledge base of global nutrient behaviour.

Read more: The importance of soil analysis – worm counts and biomass score

"It’s clear that understanding your soil and taking the right actions based on that knowledge is vital for maximising production and ensuring your business performs to its highest standard.”

Scottish soils

PAAG (the Professional Agricultural Analysis Group) estimated that two-thirds of Scottish soils are at a pH of below 6.

Earthworm population drops off at these levels, which has an impact as they’re important 'engineers' of quality soil. Soil's organic living ecosystem is vital for ongoing fertility, not just meeting environmental directives.

But it paid to be smart about it. It’s important to understand where farmers could make a noticeable difference and where they can only provide gentle management. “Soil health, in essence, is a delicate balance that should ideally grow the crop while supporting soil biology,” added Jonathan.

He estimated that almost half of Scottish soils were deficient in potassium – a key driver of yield and growth. Vast amounts are necessary in grassland to support quality grazing platforms or multiple cuts of silage.

Conversely, he estimated that two-thirds of Scottish soils could be high, or potentially excessive in phosphorous, which can cause issues when it leaches into waterways.

“Phosphorous and potassium should be informing your fertiliser choice,” he pointed out. “Challenge established ways of doing things. Maybe a balanced NPK fertiliser isn’t the right choice for you at the moment.”

By performing soil testing and opting for a broad-spectrum nutrient test, invisible deficiencies – which may be hidden to the naked eye but undercut yield potential and long-term soil health – are revealed. Action can then be taken, he argued.

“Last autumn, perhaps three-quarters of the samples we ran were below guidelines for sulphur,” said Jonathan. “Calcium is often deficient. Boron, manganese, copper, zinc … we regularly see high incidents of deficiency in all of these.”

Molybdenum is a particularly worrying example. Soil sampling at Pocklington showed significant deficiency right across the board. Molybdenum is a crucial micro-nutrient and key driver of N –especially vital in a year like this one.

“Around a third of Scottish ag soils are depleted, or at marginal levels of organic matter,” said Jonathan. “Don’t just stop at chemistry, go beyond it. Think of structure, texture, and biology.

"Without adequate supplies of organic matter to stabilise structure and act as a massive nutrient store, everything slows down. Soil testing lets you target better and gradually improve organic matter in a way that benefits your farm both in the short- and long-term. “

The pillars of soil health

Soil health is founded on three inter-linked pillars of fertility – chemical, physical, and biological.

While that first chemical pillar received a great deal of attention, it is easy for the other two to slip away forgotten. Soil analysis gives growers a holistic view of their soil so they can know where they’re strong and where they’re lacking.

“It doesn’t matter where you are,” said Jonathan. “Shortfalls exist everywhere. That’s what analysis is about… finding the limiting factor on your farm so you can address it, correct yourself, and improve moving forward.”

Growers naturally make decisions at a macro 'big field' level. However, the impact of those decisions happens at a microscopic level. Soil analysis allows us to measure that response and, ultimately, turn micro decisions into macro benefits when made correctly.

“Positive change starts beneath our feet,” added Jonathan. “Soil analysis allows us to measure our current levels and make the best choices so that we’re always heading in the right direction.”