January provides a great opportunity to plan for the year ahead and an essential starting point for any farm plan is soil test results. It is also important to remember that all farms are required to have a nutrient management plan under cross-compliance.

Knowing what nutrients are in your soil is key to all fertiliser planning for the year ahead.

Regular samples

Soil samples should be carried out regularly, every three to five years, depending on rotation and management.

The ideal time to take a soil sample is from late autumn to early spring, but in relatively dry conditions.

More regular testing can benefit your fertiliser bills. Sampling every three years may provide a balance and provide enough time to see differences occur in soil indexes, particularly on tillage farms where crops change regularly.

There are plenty of options available when it comes to sampling. Some farmers like to take the samples themselves. If doing so, a representative sample of the area should be taken in a W-shape. Approximately 20 soil cores should be taken per sample to a depth of 10cm.

If there are problem areas on your farm you might consider an individual sample, as the solution could be something as simple as rectifying soil pH.

For those with the ability to apply fertiliser at variable rates, detailed maps can be obtained from variable-rate soil sampling.

Carrying out variable-rate sampling for soil pH could be well worth the effort if your local contractor has the technology to apply lime at variable rates. Getting soil pH right can increase nutrient use efficiency and uptake and could be worth the investment.

Many advisory services will take soil samples for you, send them to the lab, analyse your results and make out a plan with you and this can often take the hassle out of the job.

The route you choose is up to you, but always use an up-to-date set of soil test results when planning for the year ahead.

Top tips

  • Regular soil sampling can help to reduce fertiliser bills and identify problems and solutions in fields.
  • Soil tests should be carried out every four to five years at a minimum. Farms receiving a nitrates derogation must carry out soil tests every four years with one sample every 5ha on ground carrying the same crop and of the same soil type.
  • A soil sample should be taken every 2ha where land is not uniform.
  • Avoid taking samples from unusual areas such as where an old drain was filled in or where farmyard manure was loaded.
  • If you spot a problem area on your farm, sample that area separately.
  • Variable-rate maps and application can be useful when it comes to soil pH and lime.