The analysis process of soil samples is a key part of ensuring that fertiliser is being used to its maximum potential, according to the Fertiliser Association of Ireland (FAI).

The third video in the association’s video series on the “Efficient Use of Fertilisers” outlines the key steps in the soil analysis process in the laboratory.

This video follows the two previous videos on soil sampling and fertiliser planning.

Commenting on the matter, Dr. David Wall said:

“In the region of 175,000 soil samples are taken across the country annually – and the winter period [November to February] is an opportune time to take soil samples across the farm to get a true reflection of the plant available nutrients in each field.”

Brendan Healy, soil laboratory manager at Johnstown Castle, outlined the key steps in the soil analysis process from start to finish.

He explained the importance of ensuring that each sample is carefully prepared and analysed and that quality control is maintained to ensure accurate soil test results at the end.

On this last point, Healy highlighted that the soil P and K results are also reported by soil index.

The soil index indicates if the levels of these soil nutrients are: (1) very low; (2) low; (3) optimum; or (4) high.

As P and K index = 3 is the target on many farms, the soil test results indicate which fields require additional fertiliser or organic manure applications to build up soil fertility.

Continuing, the lab manager said: “The soil analysis process relies on correctly taken soil samples that represent the field area sampled.

“When fully filled soil samples are sent to the soil laboratory they provide sufficient quantities of sample to carry out all the soil tests required and to generate the most reliable soil test results for each field.”

Mark Plunkett, president of the FAI, explained: “Reliable soil test results are the foundation to planning the application of lime and provides the basis for making informed nutrient [slurry, P and K] application decisions at key times during the growing season.”