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Grow the future

Farming is a way of life and is anything but predictable. That's why your farm must be efficient and resilient enough to grow crops both sustainably and profitably now and in the future.

Silage fertiliser management

Getting a good crop of grass for silage shouldn't be complicated, just a few simple steps will produce impressive results.

Avoid compromising the yield or quality of your silage by not taking chances with your fertiliser programme

Why is balanced nutrition important when growing grass for silage?

Like any crop, grass needs balanced nutrition. Nitrogen, potassium, phosphate and sulphur are all required with a large demand for these macronutrients during spring growth so it is critical that sufficient quantities of all these nutrients are available for uptake when required by the plant.

Nitrogen drives yield. Nitrogen is the major nutrient required by grass. It is the key to achieving high dry matter yields and is often strategically used to increase production as it is needed.
Phosphorus promotes growth. Even though phosphorus demand is low compared to that of nitrogen its availability is essential. Phosphate allows the plant to process light energy into biomass, so any soil availability shortfall is going to hamper grass growth rates. A deficiency of phosphorus can reduce nutritional quality and digestibility.
Potassium requirement is high. Potassium is the nutrient required in the greatest quantity by silage swards. It has a wide-ranging role in the plant affecting nutrient uptake, photosynthesis, rate of growth and feed value.
Sulphur is essential for proteins. Sulphur applications reduce grass nitrate levels at harvest improving silage fermentation. Sulphur deficiency reduces nitrogen use efficiency which will reduce yield. Sulphur will improve the protein level of grass, reducing the need for supplementary feeds.

Nitrogen

Every unit of nitrogen gives a return of 45kg of silage

Phosphorus

A 10-tonne crop of fresh grass requires 17 kg of phosphate

Potassium

You could lose 30% of your yield due to a shortage of potash

Sulphur

First cuts have a high sulphur requirement which cannot be replaced by slurry alone

So why is sulphur so important for grassland

All plants including grass 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 sward's requirement through the growing season, 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 grass has access to it throughout the growing season.

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 grass 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 grass, environment and your pocket.

No segregation

YaraMila compound fertilisers don't allow any segregation of nutrients

No compromise

YaraMila compound fertilisers require no compromises on spreader settings

Why is a compound fertiliser is so much better than a blend?

No segregation of nutrients. There is simply no segregation of nutrients during transport, handling or application. Because all the granules have consistent particle size and bulk density no segregation is possible, and each granule contains the exact same nutrient content.
No compromised spreader settings. There is no trade-off or compromise when setting the spreader, unlike when spreading a poor size-matched blend when each component may require different spreader settings.
Spread further and more evenly. YaraMila compounds are all strong granules that can easily be spread further without the risk of shattering and dust, unlike many blends which often contain weak prills prone to shatter when they are hit by the vanes.

10%

Trials show that sulphur will give you an extra 10% yield of grass

3%

On average trials show a yield penalty of 3% from using a poor quality blend

6%

An 8 day delay in application after cutting could lose you 6% in yield

So how do these figures add up?

Just a few changes can soon add up so let's look at some figures.

Yield increase from sulphur. Applying sulphur by choosing YaraMila Extragrass (27-5-5 + 6% SO₃) or YaraMila Silage Booster (20-4.5-14.5 + 7.5% SO₃+ Se) rather than using an equivalent blend will give you an extra 10% yield of silage.

Yield penalty from using a blend. Trials have shown an average yield penalty of 3% from using poor quality blends.

Yield loss due to delay. Trials have shown a yield loss of 6% due to an 8 day delay in application.

So based on these figures that means almost 20% extra silage just from a few simple changes

With a second cut yield of say 6t/acre valued at £30/t this extra yield is worth around £35 per acre. But remember that 1 tonne of fertiliser will treat 5 to 6 acres (depending on application rate), so applying a YaraMila NPKS compound is worth an extra £117 - £140 per tonne of fertiliser. But don't forget because if you delay applying by more than 8 days you could end up losing £10 per acre

Or to put it another way, a blended fertiliser without sulphur would need to be £140 per tonne cheaper than the comparable Yara fertiliser for you to just break even.

A cheap blended fertiliser is often a false economy

If you choose a cheaper blended fertiliser without sulphur rather than a YaraMila compound fertiliser it would have to be £117 - £140 per tonne cheaper just for you to break even, based on the yield response on second cut silage.

Recommended silage fertilisers

The following grassland fertilisers all supply balanced nutrition including nitrogen and sulphur and are recommended for silage.

YaraMila NK SULPHUR

22-0-14 + 7.5% SO3 - Compound fertiliser suitable for high phosphate, low potash soils deficient in sulphur.

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.

Find a local supplier