Soil analysis discovers limiting factors

UK soils have changed a lot in the last few decades; whether it’s the 97% sulphur deficiency found in soils sampled or the low organic matters across arable land. Therefore everyone knows the importance of taking a soil sample; but should you be investing in more than just basic soil analysis?

The basic analysis will give you P, K, Mg and pH; which is a good start but what about Ca, S, Mn, Cu, B, Zn, Mo and Fe? All are important to plant nutrition and you may be unaware that your soils are low in one or more of these elements. Soil sampling is about finding the limiting factors on your farm and being able to make sure they aren’t impacting upon yield – think Liebig’s barrel!

Yara’s Analytical Services have processed over 20 million samples. This huge dataset has shown that after removing all the soils with limiting factors such as P < index 2, pH <6.5 and micronutrient deficiencies then less than 20% of UK arable soils growing wheat have sufficient levels. When you look at soils sent in for oilseed rape fields then even less are sufficient.

Broad spectrum soil analysis can identify issues before it's too late

By taking a broad spectrum soil sample you’ll know about these issues before it’s too late – when symptoms appear and yield is already taking a hit. Liebig’s law of the minimum states “A deficiency of any single nutrient is enough to limit yield”. With yields being pushed further, whilst costs savings are sought (such as P and K holidays) you could be limiting the effectiveness of any increased nitrogen applications.