With the National Fertiliser Register fully in place for 2025, decisions around fertiliser use on tillage crops need extra thought and planning for the year ahead. While the fertiliser register was not made with the purpose of limiting or constraining crop output, it can become a hindrance, unless some important tasks are carried out.

Soil test

This cannot be stressed enough. A valid soil sample is required for every 4-5ha (10-12.5ac) and without this your phosphorus (P) fertiliser allowance is effectively zero. Soil samples are valid for four years, so samples taken in 2020 or older cannot be used this coming year. There are no limits on potassium (K) and sulphur (S) fertiliser applications.

Nutrient management plan

Once the soil samples are in place the nutrient management plan (NMP) will help you plan on a field-by-field basis where to spread the fertiliser and what fertiliser types should be used.

Fertiliser purchasing list

Once the nutrient management plan is completed for the farm, you will be able to determine what type and quantity of different fertilisers you can buy. It is a good idea to consult with your fertiliser supplier to see what fertiliser is on offer. Fertiliser is available in many different blends with different ratios of N, P, K and S, to best meet your crop requirements. Straight fertiliser products of P and K may also have a role to fine-tune crop allowances and to build-up soil fertility levels.

Maximising nutrient retention and availability

As specific fertiliser nutrients may be limited and fertiliser is a significant input cost on farms, attention to detail with fertiliser management and applications is important. Apply fertiliser nutrients in advance of crop demand, when soil and weather conditions are suitable. Ensure that your fertiliser spreader is properly calibrated and replace any worn parts. Don’t assume that previous fertiliser settings from last year will be the same this year. Check your calibration settings often, within batches of fertiliser purchased and across the different fertiliser products you are using, to ensure accurate applications and to maximise the final results of crops yields and nutrient use efficiency.