Sulfur fertilization – what is it worth?

Is the additional cost of sulfur fertilization well invested? The answer depends on crops and soil characteristics. Moreover, farming strategies are to be taken into account.

High quality – high yield strategies require a careful adjustment to sulfur needs.

Wheat: Increasing yield and protein

Sulfur is key when it comes to fertilization strategies that target highest quality. This figure shows the results of field trials in Germany for different scenarios. Yield and protein content were compared for mean and high nitrogen intensity strategies. The results show the potential of sulfur in high value cropping strategies. 1) Mean Nitrogen intensity, no sulfur; 2)high nitrogen intensity (+30kg N), one application of sulfur at the first dressing (+15kg S); 3) high nitrogen intensity (+30kg N), sulfur application at the first (+15kg S) and third dressing (+15kg S). Optimum nutrition enable 7% increase in protein content.

Grassland: Increasing energy

Yield, energy content, raw protein content and raw fibre content of grass silage increase with sulfur application. Split application has demonstrated superior yield performance over no or one single application. Mean yield from 3 trials in Germany. Yield increases by 3,6% with one application of 125kg sulfate (CASO4) at the first cut. If the same amount of sulfur is split between 4 applications, yield increases again, reaching 6,3% above the reference level.

Rapeseed: Sulfur demanding

Rapeseed is a demanding sulfur crop, mobilizing up to 180 kg SO3/ha. However, a significant proportion of oil seed rape crops receive no specific sulfur fertilization. Mean yield losses in case of sulfur deficiency are around 3 to 4 q/ha but can reach 15 to 20 q/ha in case of severe deficiency. The optimal sulfur fertilization rate is 75 kg/SO3.

Enhacing yield and returns

A great number of field trials have proven the benefits of tailored N/S fertilization on various crops. For most crops, yield and additional gross income increases significantly when using N/S fertilizer