How Much Silage Do I Need for Winter?
Planning silage stocks before winter is one of the most critical management decisions of the year. Run short and you're buying expensive forage in February. Run long and you've tied up cash unnecessarily. Here's how to get the numbers right.
Quick answer
For a 20-week winter, plan for 7–8 tonnes per dairy cow and 4–5 tonnes per beef animal — before wastage. Add 12–15% for clamp and feed-out losses. The calculator below gives you the exact tonnage for your herd.
Quick Silage Requirement Calculator
Per head
6.3 t
Total (no waste)
315 t
With 13% wastage
356 t
Based on average fresh weight intake by livestock type. Assumes 25–28% DM grass silage. Always check against your own yield records.
Silage Requirements by Livestock Type
| Livestock type | kg / day | 16 weeks | 20 weeks | 24 weeks |
|---|---|---|---|---|
| Dairy — high yielding | 52 kg | 5.8 t | 7.3 t | 8.7 t |
| Dairy — average | 45 kg | 5 t | 6.3 t | 7.6 t |
| Suckler cow | 38 kg | 4.2 t | 5.3 t | 6.4 t |
| Beef — finishing | 32 kg | 3.6 t | 4.5 t | 5.4 t |
| Beef — store | 22 kg | 2.5 t | 3.1 t | 3.7 t |
| Young stock | 15 kg | 1.7 t | 2.1 t | 2.5 t |
Figures are tonnes fresh weight per head, before wastage allowance. Add 12–15% for clamp losses. Source: AHDB Dairy/Beef guidance.
Why you need more than the theoretical figure
The table above gives theoretical intake — what a cow consumes at the feed face. In practice, silage clamps lose 8–15% to spoilage, shoulder waste and feed-out losses. Baled silage is typically higher, especially if bales are damaged or stored poorly. A sensible planning rule is to multiply your calculated requirement by 1.13–1.15 to build in a buffer.
Dry matter matters more than fresh weight
Cows eat to a dry matter intake target, not a fresh weight target. If your silage comes in at 22% DM rather than 28%, cows will eat more kg to hit their energy requirements — and your silage will run out faster. Always test DM% at clamp opening and adjust feeding rates accordingly. A dairy cow targeting 14 kg DM/day from silage needs 50 kg of 28% DM silage, but 64 kg of 22% DM silage.