Agronomy Advice
June 01, 2024

Sulphur: Best Practice

By: Natalie Wood

It is widely accepted that UK soils are deficient in sulphur so supplementation via organic manures or mineral fertilisers is essential. What I think is less understood is that not all sulphur-containing fertilisers are the same. Moreover, there is varied advice around application timings and how much sulphur is required for best results.


Canola Fields
Canola Fields

Are you spreading the right type of sulphur?

Make sure you select fertiliser that contains sulphur in the sulphate form, this will ensure that the nutrient is readily available for your crops to take up. Crops cannot take up elemental sulphur, it must first be converted into sulphate by soil microbes, delaying the impact it will have on your crops, affecting growth and yields.

Can you apply straight N followed by a separate sulphur product?

Whilst this is one approach you can adopt, we would recommend against it. Instead, we suggest applying a compound fertiliser like YaraBela Axan which contains the right ratio of sulphur and nitrogen, providing growing crops with just the right amount of nutrition to maximise growth and quality.

You’ll also save money on reduced passes required in spreading sulphur and nitrogen as one product at the same time.

Why should I spread sulphur little and often?

Sulphur easily leaches in the soil, so applying it all in one go would result in large losses of the nutrient. It’s similar to nitrogen in this way, so just as you apply nitrogen little and often throughout the season, we do the same with sulphur to ensure that there is always a ready supply of the nutrient to our crops. By applying it at the same time as nitrogen throughout the growing season you’ll also improve your nitrogen use efficiency due to their synergistic relationship.

Are there different sulphur requirements depending upon my crop?

Yes, it tends to depend upon the vegetative period of your crops. Crops with a short vegetative period will need high amounts of sulphur in a short period of time whilst crops with a longer vegetative period have more time to recover sulphur from the soil so are less dependent on sulphur derived from fertiliser or manures. Oilseed is particularly demanding when it comes to sulphur so deficiencies in this crop can lead to losses of up to 1 or 2 t/ha.

Crop Sulphur Recommendation
Oilseed rape 75 - 100 SO3/ha
Winter Cereals 40 - 50 SO3/ha
Spring Cereals 20 - 26 SO3/ha
Grassland (Silage) 40 kg SO3 Cut / ha per cut
Grassland (Grazing)

10 kg SO3 /ha per month

 

Things to remember when it comes to sulphur

  • Sulphate is the best form of sulphur as it’s immediately available to plants
  • Sulphur improves nitrogen use efficiency
  • Because sulphur leaches, it’s best applied in the same way as nitrogen: little and often
  • Trials have shown that little and often application of sulphur improves yield responses.
  • Compound NS fertiliser grades provide accuracy of nutrition and cost savings in application