Red Clover Silage
Silage crops are fertiliser-hungry and often inefficient.
Red clover cuts nitrogen needs and produces high-quality, protein-rich forage for silage.
The Climate Issue
Silage is essential for winter feeding. But growing it comes with high emissions. Grass silage needs lots of nitrogen, up to 300 kg N/ha in some systems. That fertiliser emits nitrous oxide, ammonia, and increases the risk of nutrient runoff.
High-input silage systems also degrade soil structure, reduce clover content, and deliver variable protein levels. And during cutting and wilting, extra passes with machinery raise fuel use and cost.
That makes silage one of the most emission-intensive parts of dairy feeding.


The Solution: Red Clover
Key Benefits when using Protected Urea
Cut Emissions
Red clover fixes nitrogen, reducing reliance on synthetic N. That lowers GHG emissions and ammonia loss from fertiliser spreading.
High Protein
Red clover silage delivers more dry matter and higher protein than grass-only silage, supporting milk solids during winter feeding.
Soil Health
Its deep roots boost soil structure, resist drought, and add organic matter back into the soil, making it a regenerative option for forage.
Impact of Switching to Protected Urea
Research shows that red clover can:
- Replace up to 200 kg N/ha in silage crops
- Deliver €100–€200/ha in fertiliser savings
- Cut emissions by 5–10 %
- Improve milk yield and solids in housed periods

Scenario
|
Red Clover Area
|
Fertiliser Savings / 20 ha
|
GHG Emissions
|
% GHG Reduction
|
---|---|---|---|---|
0% Silage Area |
- |
- |
0.960 kg CO₂-eq/kg milk |
0% kg CO₂-eq/kg milk |
50% Silage Area |
10 ha |
€1,000 |
0.921 kg CO₂-eq/kg milk |
4.1% kg CO₂-eq/kg milk |
100% Silage Area |
20 ha |
€2,000 |
0.881 kg CO₂-eq/kg milk |
8.2% kg CO₂-eq/kg milk |
Considerations
Lifespan & Rotation
Red clover is short-lived, typically 3-4 years. It suits silage rotations but should be managed to avoid overgrazing or damage in wet conditions.
Cutting Management
Red clover silage should be cut before full flowering. Delayed cutting reduces quality. Avoid cutting too low to preserve regrowth.
Bloat Risk & Inclusion Rate
When grazed (not typical), bloat can be a risk. Stick to silage-only systems or manage carefully in mixed swards.

Implementation
- Choose a suitable site. Avoid poached or heavily trafficked fields. Select paddocks due for reseeding and rotate every 3–4 years.
- Prepare and sow. Aim for pH 6.3+, and Index 3 for P and K. Sow in spring or early autumn with a suitable grass companion (e.g. Italian ryegrass).
- Cut correctly. Take the first cut before flowering. Leave a 6 cm stubble to protect crowns. Apply slurry after cuts—red clover needs no additional nitrogen.
Behind the Research
ODOS Tech was founded by Cian White and Alejandro Vergara, two sustainability specialists with deep expertise in agricultural climate action.
Cian, a researcher at Trinity College Dublin with a background in environmental science, works on restoring nature to increase biodiversity on farms by using satellite images to track trees, hedgerows, and other habitats. Alejandro, a PhD researcher at University College Dublin, helps farmers measure their carbon emissions footprint and implement mitigation strategies to reduce their impact.
Together, they helped lead the carbon and nature-based work for the Farm Zero C project at Shinagh Farm, one of Europe’s first net-zero dairy pilots. At ODOS, they build smart, science-based tools to help agri-food businesses protect the environment and restore nature.

Research
Teagasc Red Clover Silage Trials
Teagasc trials show red clover yields match or exceed conventional silage, even with 70 % less synthetic N. Crude protein is 2-3 % higher than grass-only silage.
Farm Zero C Implementation
At Shinagh Farm, red clover was integrated into silage areas with strong results – lower fertiliser use, improved forage quality, and steady milk production over winter.
Policy Support
Red clover is supported under many eco-schemes for nutrient efficiency. It aligns with EU and CAP targets for reducing fertiliser inputs while maintaining feed quality.
Ready to reduce emissions through Red Clover Silage?
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