Nitrogen and sulphur should be applied together
When you apply nitrogen and sulphur together it increases your nitrogen use efficiency so means you get more yield for your money with less wastage
A lack of sulphur reduces nitrogen use efficiency, meaning that crops do not make good use of nitrogen as the two nutrients work hand-in-hand
How common is sulphur deficiency?
85%
of arable soils are deficient in sulphur
88%
of grassland soils are deficient in sulphur
25%
of grain samples are low in sulphur
- Based on samples received at Yara Analytical services in 2019 85% of arable soils and 88% of grassland soils were deficient in sulphur
- Based on grain samples analysed in 2019 almost 25% of samples were below 0.12% S indicating the crop was suffering from a sulphur deficiency which will have resulted in a loss of yield.
So why is sulphur so important
Plants need sufficient levels of sulphur to be able to utilise nitrogen efficiently. Together, nitrogen and sulphur are vital building blocks for protein, so N and S should be applied at the same time.
Sulphur behaves in a very similar way to nitrogen in the soil, readily leaching in the sulphate form just as nitrates do therefore this should dictate that you’d treat it the same as nitrogen. You wouldn’t apply all your nitrogen in one go and expect it to fulfil the crop requirement through the growing period, so why treat sulphur like this? Applying sulphur in one application means that there is a large potential for a lot of it to leach away through the soil profile and is then not available to the crop. Applications of sulphur little and often, as you would with your nitrogen, ensures that the crop has access to it throughout the growing season.
In terms of sulphur affecting quality, in cereals, the number of grain sites and the size of the grain is reduced, with lower grain protein also resulting from sulphur deficiency. Whilst symptoms appear too late for effective treatment, the majority of crops will respond to the timely application of sulphur with both increased yields and improved quality.
Another reason to apply sulphur little and often along with your nitrogen is that there is a very close relationship between the two nutrients. As mentioned, nitrogen can’t be taken up and utilised effectively by the crop unless there is a sufficient supply of sulphur present. With more and more emphasis being put on increasing nitrogen use efficiency (NUE) on-farm then this is one easy way to start to do that. Ensuring there is sufficient nitrogen and sulphur at each application means the two nutrients work together which is better for the crop, environment and your pocket.
What's the best way to apply nitrogen and sulphur?
Sulphur should always be applied at the same time as nitrogen
Sulphur should be applied 'little and often' through the season
- Plants need a regular supply of sulphur throughout the growing season, so a 'little and often' approach to sulphur management is essential.
- Sulphur is immobile in the plant so cannot be moved from old to new leaves when it is needed, this means fresh sulphur is still needed later in the season.
- Sulphur can be readily leached through the soil, just the same as nitrogen, so shouldn't be applied 'all at once'.
- Nitrogen deficiency is easily confused with sulphur deficiency so if you think you are seeing nitrogen deficiency on younger leaves it is probably caused by a lack of sulphur.
Don't waste your money on more straight nitrogen
To grow efficiently both nitrogen and sulphur are needed by plants, so there is little point spending more money on nitrogen if you haven’t spent enough on sulphur.
How much straight nitrogen do I actually need?
When new prices come out, on-farm discussions often revolve around the price of nitrogen but before going ahead and ordering it is crucial to ensure you actually buy what you need. It is tempting to buy what you think is a bargain at the time but first ask yourself ‘how much straight nitrogen do I need?’
This may sound obvious, but it is always surprising when next spring comes along, as to the number of discussions that will take place as to how to use this pile of nitrogen that had been purchased when actually NPKS and NS were also required.
As a guide, 50-75% should be in the form of a nitrate plus sulphate fertiliser and 25% will be in the form of an NPKS true uniform compound fertiliser.
Can you afford to ignore sulphur deficiency?
£5
Every £1 spent on sulphur gives £5 extra yield
2t/ha
Adding sulphur can boost cereal yields by upto 2t/ha
£112/ha
Sulphur deficiency could cost you £112/ha
- Based on recent trials the return on investment in sulphur ranged from £2 to £10 per ha with an average of £5 return in extra yield
- Yield responses to sulphur can vary season to season with 0.2 - 1.9t/ha seen in recent years across cereals and oilseed.
- Based on current prices, sulphur deficiency this year could cost you £112/ha
How much sulphur do I need and what difference will it make?
In terms of rates of sulphur then cereals require about 40-50kg SO3 and oilseeds require about 75-100kg SO3. However tissue analysis is a reliable indicator of deficiency in the growing crop and, of course, you will have all the nutrient, as well as sulphur, results back. Guidelines levels for sulphur content in wheat tissue is 0.40% and 0.25% in oilseed tissue.
Another analysis that can be carried out is grain analysis; this is a good way to look back on your nutrient strategy and see whether it has worked as intended. In the grain, sulphur results are given as a percentage within the grain but also as the N:S ratio. A ratio lower than 17:1 indicates an adequate sulphur status, with a ratio of 14:1 indicating the optimum. Grain sulphur content should be maintained at 0.12%. Nitrogen status in the grain should ideally be maintained at 1.9% N for feed wheat and 2.1% N for milling wheat.
Yield responses to sulphur can vary season to season with 0.2-1.9t/ha seen in recent years across cereals and oilseed, but the type of sulphur applied is also important. If applying elemental sulphur it can take a long time (up to 8 weeks) to undergo conversions in the soil before becoming sulphate, which is the form that the plant can take up. Whilst plant leaves can absorb sulphur from the air as sulphur dioxide (now only very low levels) plant roots can only take up sulphates. So, of all the possible sources – soil reserves, organic manures and mineral fertilisers - only sulphate mineral fertilisers offer a reliable method for preventing deficiency. All others require mineralisation before becoming available to plants, therefore applying a product where the sulphur is already in the sulphate form will give you immediately available sulphur and will also contain nitrate (as ammonium nitrate) because we need both nutrients together.
In terms of the return from using sulphur then using the yield responses mentioned, an NS product can give a Return on Investment (ROI) of between £2 and £10 for every £1 invested, a better ROI than straight nitrogen alone.
How does fertiliser contribute to sustainability?
Economic sustainability
Harvesting enough crop yield to make a profit
Environmental sustainability
Making efficient use of natural resources
Societal sustainability
Growing sufficient quality food to feed everyone
YaraBela fertiliser and sustainability
Sustainability can be defined in many ways but in general terms, it is all about managing today’s requirements without impacting on the ability to meet tomorrow’s needs. It can also be split into three dimensions: economic, environmental, and social. The first two of these, economic and environmental, are very clearly linked to YaraBela fertilisers.
Economic sustainability
Considering the economic dimension, or sometimes referred to as ‘profit’, then this is very relevant to farm profitability. In a recent wheat trial, YaraBela Axan increased yield by 165% taking a crop from 7.26 t/ha to 12.01 t/ha. This profitability improvement equated to £698/ha. In YaraBela Axan each and every granule supplies nitrogen and sulphur in an immediately available form for efficient crop uptake. The sulphur element is very important with many soils and consequently crops, being deficient. YaraBela Axan, with its ideal nitrogen sulphur ratio, delivered an extra 0.43 t/ha in yield compared to a straight nitrogen application (Yara 2020 trial), improving profitability by £50/ha. The extra revenue achieved through investing in YaraBela Axan comes from the targeted application to meet the crops season-long demand for nitrogen and sulphur, alongside the accurate, even spread of nutrient that is achieved at the point of application.
Environmental sustainability
Naturally, it is important that this ‘profitability’ doesn’t come at the expense of the environment. An environmental measure that can be used towards improved sustainability is resource efficiency. An example here is Nitrogen Use Efficiency (NUE) which in arable crops can be targeted at 80%. When this is calculated for the YaraBela Axan applications described above, then the NUE% was improved by 2%. Achieving the optimum nitrogen rate is also key for sustainability, thus reducing losses in the nitrogen cycle. Nitrogen management tools such as the N-Tester BT and N-Sensor can be used to determine application rates. By using these diagnostic tools seasonal nitrogen uptake can be monitored enabling ‘fine-tuning’ of nitrogen applications. A crops nitrogen uptake will vary between years, fields and within fields. This variation in uptake is a consequence of variation in soil nitrogen supply, crop growth and prevailing weather conditions. By taking in-season measurements with N-Tester BT, atfarm or N-Sensor then dynamic nitrogen management decisions can be made, ensuring optimum nitrogen applications are made. In a four-year trial series taking such an approach delivered an extra 7% yield, whilst using 13% less nitrogen fertiliser, clearly demonstrating an improved nitrogen use efficiency. Another Yara investigation in 2017 compared ‘dynamic nitrogen management’ through the use of N-Tester with ‘static’ management where no change was made to the pre-season plan. In this trial, the N-Tester improved nitrogen use efficiency by 14.5%, with the best NUE coming from the N-Tester at 74%. Such large improvements clearly minimise the environmental impact associated with surplus nitrogen applications.
In recent years ammonia is at the forefront of many discussions, and with agriculture being the major contributor then it is important to understand what positive actions can be taken to mitigate this issue. It is estimated that costs that can be attributed to ammonia in the UK are € 542,883,212. This is predominantly the costs associated with poor human health caused by ammonia emissions. The YaraBela products (i.e. ammonium nitrate (AN) and calcium ammonium nitrate (CAN)) have the lowest ammonia emissions of all the common nitrogen fertilisers
As well as the human health issues, ammonia has a negative impact on a number of key ecosystems that are considered important towards sustainability, thus reducing the emissions through fertiliser choice has further benefits.
Another consideration regarding environmental sustainability is the nitrous oxide emissions during fertiliser production. Yara were instrumental in the development of the ‘abatement’ technology that removes over 90% of the N2O emissions that occur during the nitric acid production stage of manufacture, significantly reducing the carbon footprint. All YaraBela products are manufactured in ‘abated’ factories giving them industry-leading, certificated, low carbon footprints.
Societal sustainability
The third pillar of sustainability is the societal component that a product can deliver. Food security and poverty are clearly humankind gains associated with fertiliser. It has been calculated that mineral fertiliser nourishes 48% of the global population and has saved 2.7 billion lives over the last hundred years.
As society now looks to mitigate ‘climate change’, further reductions in carbon footprints need to be made if ‘net zero’ targets are to be achieved. Yara is investing in a number of innovations, including ‘green ammonia’ that will ‘decarbonise’ fertiliser further adding to its current sustainability profile.
Accurate spreading needs consistent quality fertiliser
YaraBela fertilisers consistent quality means they can be reliably spread more accurately and more evenly over wider bout widths
YaraBela fertilisers enable accurate spreading of all nutrients
- YaraBela fertilisers are all uniform whereas blends tend to be quite variable and come in different shapes, sizes and densities.
- Uneven application of nutrients can occur when spreading a blended fertiliser as a result of physical segregation
- Spreader calibration with blends is always a compromise due to the different ballistic properties of various constituents.
- Changing to a YaraBela compound fertiliser containing sulphur and nitrogen will ensure an even spread of both nutrients
- There are up to 6 times more sulphur landing sites with YaraBela Axan compared to Ammonium Sulphate.
What do other farmers say about Axan?
Eurig Jenkins, Pentrefelin Farm, Lampeter, Wales
"When using YaraBela Axan, you split the bag it's always quality product and we never seem to get any stripes so the quality of the grass is as good as we can produce here"
David Parke Castlewellan, Northern Ireland
"Consistency and keeping quality in storage means Yara Axan always spreads well and the spinner keeps clean even when some fertiliser is kept to be spread later. Spreading YaraMila with its consistent bulk density and particle size means a near-perfect pattern can be achieved".
Andrew Reed Berwick upon Tweed, England
"Here on our farm, I find the Yara Axan is ideal for what we are trying to get out of the crop. We only use Axan, so all the nitrogen is given to all crops with this fertiliser and the sulphur in Axan allows us to be applying sulphur each pass, which I believe is as key as the nitrogen "
Why does YaraBela fertiliser spread so well
When you purchase YaraBela fertiliser, you’re buying into a quality guarantee. This guarantee doesn’t mean just one thing. It’s guaranteeing that a number of processes from manufacture to delivery on your farm have achieved a quality standard that farmers have come to expect from bag to bag and from year to year from YaraBela.
What’s on the bag is in the bag. Because YaraBela fertilisers are manufactured at Yara plants, the nutrient and physical specifications are checked for every batch. These quality control safeguards ensure that every cargo of YaraBela fertiliser delivered to the UK contains the nutrient analysis it should. Yara’s bagging facilities in the UK then follow stringent protocols to ensure that the weight of product in every bag is correct and is not below the net weight printed on the bag.
The physical characteristics of YaraBela fertilisers are the reason why they spread so evenly, even on 36 m tramlines. The key to this is the size, shape and strength of the fertiliser granule. The size range is carefully controlled during manufacture, and those granules that are over or undersized are screened off. The shape of the granules is smooth and round which means they bounce off the vanes of the spreader more predictably. YaraBela granules are strong enough to withstand the impact of the vanes when they hit them. Bear in mind, that increasing spreading width, increases the relative importance of this characteristic on spreading accuracy.
Remember, the effects of uneven spreading remain invisible in most cases. Only drastic variations are visible as dark and light stripes. However, losses set in long before any variation becomes visible to the naked eye. The cost of uneven spreading is mainly due to lost yield and lost quality. The physical characteristics of the fertiliser you chose will have a decisive impact on spreading performance and precision.
See for yourself the effect of physical properties
- The bulk density and strength of fertiliser both determine how far a fertiliser can be spread accurately
- This demonstration shows the effect that bulk density has on the spreadability of fertiliser, in other words 'why heavier fertiliser spreads further
Can you afford not to use quality fertiliser?
- Even application of nutrients means more even crops, resulting in less lodging, reduced drying costs and smoother harvesting.
- Reduced spreading variability results in an even crop and increased yields (co-efficient of variation or cv of 10% with YaraBela vs 34% typical of blended fertiliser).
- Ability to spread accurately over wider bout widths saves time spent spreading and reduced application costs.
Stronger
YaraBela granules are stronger so will not shatter when spread
Wider
YaraBela fertilisers will all easily spread to 36m and beyond
Heavier
YaraBela granules are heavier so perform better even in windier conditions
All YaraBela fertilisers are granular compounds
- Because all YaraBela fertilisers are granules they will all easily spread up to 36m and beyond.
- Because YaraBela granules are stronger they will not shatter when you spread them giving you a cloud of dust.
- Because YaraBela granules are heavier they will spread better under windier conditions giving a more even application.
- Remember if it doesn't say Yara on the bag it won't be Yara quality fertiliser in the bag.
- Yara doesn't sell fertiliser in anyone else's bags.
Recommended nitrogen plus sulphur fertilisers
The following YaraBela fertilisers contain nitrogen plus sulphur and are recommended for all crops.
Improve your farm's nitrogen fertiliser efficiency
Improving nitrogen fertiliser efficiency is one way your farm can become more productive, profitable and sustainable. Try our quiz to find out how you can improve your farm's nitrogen fertiliser efficiency.
Where can I buy Yara fertilisers ?
Yara supply our solid and liquid fertilisers and micronutrients through a network of local suppliers Use our interactive map to locate your nearest suppliers.
Read more about improving nutrient efficiency
Future-proof your farm
Find out how your farm can become more productive, profitable and sustainable by future proofing your resources, your profit and our planet.
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