What is Silage Time?
Silage time is one of the busiest and most important events on a dairy farm. It’s when surplus grass is harvested and preserved to feed cows during the winter months, when grazing isn’t possible. Here’s what happens during silage time:
The Silage Process
• Silage is usually made in late spring or early summer, once grass growth is strong and the first grazing rotation is complete.
• The goal is to harvest high-quality grass at the right stage — typically before it becomes too stemmy — to ensure good nutritional value.
• Silage is essential for feeding cows during the dry period (winter) when pasture is limited or unavailable.
• Fields are often closed off several weeks in advance, meaning cows are kept off to allow the grass to grow.
• Farmers may fertilize fields with slurry or nitrogen to boost growth.
• Machinery is checked and serviced, and contractors may be booked in advance if the farm doesn’t do its own harvesting.
• When the weather forecast predicts a few days of dry, settled conditions, silage-making begins.
• Grass is mown, then left to wilt in the field for 24–48 hours to reduce moisture.
• It is then raked into rows and collected using a forage harvester or silage wagon.
There are two common ways to store silage:
• **Clamp silage:** The cut grass is brought to a concrete pit (the clamp), spread in layers, and tightly rolled to squeeze out air.
• **Baled silage:** Grass is baled into round or square bales and wrapped in plastic to ferment individually.
In both cases, the aim is to create anaerobic conditions (no air) so the grass ferments properly and doesn’t spoil.
• Once sealed, the grass ferments over several weeks, turning into silage — a sour-smelling, moist, preserved feed.
• This fermentation process locks in nutrients and makes the silage stable for storage over winter.
• High-quality silage is crucial for maintaining cow health and body condition during the non-grazing season.
• On spring-calving farms, silage supports cows during their dry period and early lactation if grass is not yet fully available.
• It’s the second-most important feed after grass — and the best way to make sure cows stay productive year-round.
In Summary
Silage time on a spring-calving, grass-based dairy farm is all about capturing the goodness of spring and early summer grass to feed cows through the winter. It takes planning, good timing, and teamwork — and the quality of the silage made can have a big impact on the farm’s success in the months that follow.