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Current Farm Advice:

Read the latest farm advice and current actions farmers should consider taking

Climate Actions for February

Three reasons to use Protected Urea in 2023

Use protected urea, it's cheaper than CAN or standard urea and delivers 13% higher yield than straight urea.

Reason 1. Protected urea is cheaper than CAN and straight urea

Protected urea is cheaper than CAN on a cost per kg of nitrogen basis, and, while it may appear slightly dearer than ordinary urea, it will give the same “effective N” as urea, at a 12.5% lower spreading rate.

 Table 1 summarises the N lost from the three N fertiliser products as ammonia and nitrous oxide nitrogen gases. The EPA estimates that ammonia loss from urea is 15.5% on average. Both protected urea and CAN having lower rates of N loss (79% reduction for protected urea = 3.3% loss; 85% reduction for CAN = 2.3% loss). Published research has quantified direct N loss as nitrous oxide from urea (0.25%), protected urea (0.4%) and CAN (1.49%). In summary, protected urea curtails N losses by reducing (1) ammonia N emissions compared with straight urea, and (2) nitrous oxide N emissions compared to CAN. This would make protected urea more cost effective than both urea and CAN as spread.


While the cost per kg of nitrogen is cheapest for straight urea (Table 2), when the extra losses associated with straight urea are accounted for, protected urea is cheaper. See example 1 below.

Table 2:           Relative Cost per kg N for Different Fertiliser Types

Example 1
Assuming a rate of 50 kg of N spread as protected urea or 50 kg of N spread as CAN in March 2023. The equivalent quantity of N as straight urea that would need to be spread is 57kg, allowing for the extra losses with straight urea. If we assume costs of urea = €950/t, protected urea = €1,000/t, CAN = €750/t, Table 2 highlights the difference in cost with protected urea being the cheapest option.

Table 3:           Relative Cost per kg N for Different Fertiliser Types

At these prices, the farmer will get better value for money by using protected urea (as opposed to urea). The example above, using current fertiliser prices, shows that the extra cost of the urease inhibitor more than covers its cost, if it saves 7 kg of N. The value of retaining N that had previously been lost as ammonia has increased dramatically in line with the increased fertiliser cost. Also, in a situation where N application rate is limited, it makes sense to use less of a more effective product.

Reason 2

The quantity of grass grown by using CAN, protected urea and urea will be similar across all fertiliser types.

In a long-term trial at Johnstown Castle, the grass grown by the protected urea was 13% ahead of urea on average over 6 years (drought year excluded).

Reason 3

By switching to 100% protected urea on dairy farms, total farm emissions have the potential to be reduced by 7-8% at a spreading rate of between 200 to 250 kg N / ha. The equivalent savings on total emissions on suckler farms is 1-2%, at a spreading rate of 60 to 80 kg N / ha. Straight P and K fertilisers or blends such as 07-30 or 010-20 may need to be used with protected urea to balance nutrient requirements.

Table 4:          Benefits of using different fertiliser types

Get your slurry analysed for nutrient content 

Knowing the quality of your slurry can help make decisions on application, ensuring its use is optimised and not wasted.  Use a hydrometer to estimate the nutrient content of your slurry.  Check out this video which explains the process Measuring slurry with an Hydrometer  

Alternatively, send a sample to a laboratory for analysis.  The procedure for taking a slurry sample:

  • Your own health and safety is the first most important aspect. Be aware of safety guidelines around PTO guards and slurry gases.
  • January/February i.e. the first time slurry is being spreading after the winter is the best time to test slurry
  • The slurry must be well agitated so that all crust and water are completely mixed before taking the sample
  • Suck up a load of slurry from the slurry pit using the slurry tanker
  • Get the slurry sample from the fill point of the slurry tanker
  • Place 0.5 litres of slurry into a sealed screw-capped container provided
  • Keep the sample cool and post to the lab the day you take the sample
  • A number of slurry tanks should be tested if both covered and uncovered slurry tanks are in the farmyard

Spreading Slurry

Spread slurry close to when grass growth is taking off using LESS equipment. Save good quality slurry for silage ground which has the biggest demand. Read here for more on Organic Manure

Continue to spread Lime

Continue to spread lime through February to save up to 80 kg N/ha. Read here for more on Advice on Liming

 Grazing animals feed themselves and spread their slurry

Feeding your animals, avoiding poaching, and grazing out paddocks are three golden rules for spring grazing and should be considered in that order. Every day at grass is worth €2.70 per dairy cow and €2/LU for drystock farms. Not to mention saving on the amount of fodder required to make for next winter. Here are some tips to ensure you earn more money this spring through early grazing.

The Grass:

Let stock out to graze on the right grass covers. This means lighter covers first, not the heavier ones. Ideally let animals graze covers 600-800 Kg DM/ha (7cm) for the first few weeks (between 1 and 2 fists high of grass as guide if not familiar with measurements).

The Paddock:

When deciding which paddocks to graze first, choose ones closer to the yard, drier (walk to check conditions underfoot), sheltered, and square in shape. Avoid soft paddocks (unless good ground conditions).

The Infrastructure:

Ensure the paddocks you choose to begin grazing have multiple access points ideally from a hard-surfaced roadway. Be prepared to strip-graze and back-fence to avoid poaching and utilise grass. Be mindful of access to water also.

The Animal:

Early grazing usually means ground conditions are tender in places. To reduce the risk of damaging soil and swards let out younger/lighter animals to graze first. They can adapt to grazing quickly and graze through area at a much lower risk. On-off grazing may be a good option for farms carrying heavier livestock.

The Farmer:

Most important influence on getting out grazing early is the farmer and their mind-set. Being flexible is the name of the game here. Cattle can go in and out and to achieve early grazing this is likely to happen at some point. Being open to this and ready for it is key!