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Sulphur; optimising growth and quality

How to prevent Sulphur deficiency in your crops.



Sulphur is an essential component to ensure optimum yield and consistent quality of arable and forage crops.


Along with NitrogenSulphur is vital in protein synthesis and without adequate supplies, plant protein production is compromised which reduces yield.

Environmental concerns regarding industrial emissions and acid rain have led to a tightening of regulations that has seen a dramatic drop in sulphur from the atmosphere by a factor of seven.

The youngest leaves are most affected by Sulphur deficiency. In oilseed rape for example, visible symptoms are yellowing of leaves and/or pale flowers.

Beware Sulphur deficiency can be a limiting factor effecting productivity on farms throughout the UK!


Crops most at risk

As atmospheric deposition of Sulphur continues to decline, the reality is that a wide range of crops will be a risk including cereals, oilseed rape and grass. Oilseed rape, and grass grown for silage are particularly sensitive to Sulphur deficiency.

According to the British Survey of Fertiliser Practice nearly one third of farmers are still not applying Sulphur to oilseed rape and nearly half to wheat. Our range of Nitrogen Sulphur products, including DoubleTop, SingleTop, and our extensive range of compounds fertilisers offer an excellent system to counter this.

Clive Deeley, Regional Business Manager for the East


Soil types most at risk

    Winter rainfall (November- February)
Soil Texture  Low (<175mm) Medium (<175-375mm)  High (>375) 
Sandy High   
Loamy & course silty  Low High  
 Clay, fine silty or peaty  Low  Intermediate



How can Farmers correct a deficiency?

Sulphur application rate for crops


The need for Sulphur is indisputable. Applying the optimum amount of Sulphur fertilisers is dependent upon the crop and its deficiency status.

For example, trials have shown the optimum rates of Sulphur for oilseed rape should be a minimum of 60-80kg SO3/ha* and for wheat 50kg SO3/ha**.  However, in some instances there is still a worrying gap between the actual rates applied and optimum rates required. 

Analytical tools

Soil analysis isn’t always a good predictor of available Sulphur because it is highly mobile in the soil. The malate: sulphuate tissue analysis is often a better predictor of deficiency. It measures the ratio of malate and sulphate in the tissue, providing an accurate diagnosis that can be completed early in the season to allow for timely application.

Our Crop Nutrition Team are always available to give you specialist advice on either of these diagnostic methods, simply call +44 (0)151 357 5758 or contact us on email

CF Fertilisers have the solution; with our excellent range of market-leading Sulphur- rich products to maximise productivity.

DoubleTop® and SingleTop®  are high quality granular compound fertiliser that deliver all the nutrients to your crops in an even and accurate spread. Whatever strategy you adopt to apply Sulphur you can be sure that applied at the right rate and time will optimise yield and productivity.

To find a blueprint for your crop fertilisation use our Fertiliser Selector


The benefits of Sulphur

Recent work undertaken on Sulphur in oilseed rape, funded by the HGCA and conducted by ADAS on behalf of a consortium of interested parties, measured yield increases of up to 5t/ha where sulphur was applied. To protect yield and quality it is advised to annually apply a sulphur containing fertiliser such as DoubleTop® or SingleTop® .


Key Facts

  DoubleTop   SingleTop Heartland Sulphur®
Nitrogen (N%) 27  27  24
Sulphur (SO3%) 30 12  8

SINGLE application. Oilseed rape and cereals 

ALL SEASON APPLICATION little and often on cereals. ALL SEASON APPLICATION on cereals, also supplying spring P(8%) & K(8%)
Spreading Tip When applying any Sulphur based fertiliser, wipe the spreader vanes with a clean cloth and WD40 (or similar) after every two tonnes applied.   
Ammonium Nitrate Ammonium Nitrate (Nitram®) is the efficient and predictable form of Nitrogen for UK growers.    
Form of Sulphur The Sulphate form offers a readily available source of Sulphur to the growing crop.  Elemental Sulphur cannot be taken up directly by crops and has to be converted to the Sulphate form before crop uptake.   
True granular products In all CF Fertilisers Nitrogen and Sulphur products, each granule contains both elements to ensure even and accurate application across the crop.   
Conversion factors

To convert elemental Sulphur declaration to sulphate (SO3), multiply by 2.5

For example: 100kg/ha of SO3=40kg/ha elemental Sulphur.   


For more information on the difference that Sulphur could make to your arable crops download our advice leaflet

Don't forget the difference that Sulphur can make to grassland areas- our advice is available here.

For more advice on Sulphur deficiency in your crop contact our Crop Nutrition Team on +44 (0)151 357 5758 or email