Beef Management: silage fertiliser advice and turnout tips

In this week's beef management notes Adam Woods takes a look at silage fertiliser, selling cull cows and tips for turnout

Adam Woods

12 March 2025

Beef Management: silage fertiliser advice and turnout tips

Cattle continue to be turned out with a dry week helping ground conditions in many parts of the country.

Silage fertiliser: While it’s still probably early to be talking about silage fertiliser, it’s important to have it in the yard and ready to go once the weather window comes and ground conditions improve. For some farmers in the south of the country, ground conditions may be OK by the end of this week and it could be an opportunity to spread early and get an early cut of good-quality May silage. Nitrogen (N) is a key driver of grass growth and is essential to a good silage crop. Aim to apply 80 units/ac of N on silage fields.

Nitrogen (N) is a key driver of grass growth and is essential to a good silage crop. Aim to apply 80 units/ac of N on silage fields.

Recently reseeded swards have a greater ability to use nitrogen and are more efficient at converting N to grass. Silage swards will use about two units/day, so leave about 50 days between application and cutting. Phosphorus (P) and potassium (K) are essential for grass growth and it’s important that silage fields have adequate P and K to grow a good silage crop. Assess your most recent soil sample results to determine what is needed. This gives you the best chance of matching up nutrients with requirements. Cattle slurry is usually applied to silage fields in spring and can be a very good source of P and K. A rate of 2,500 gallons/ac of cattle slurry will supply sufficient P and K to grow a silage crop. In 2,500 gallons of typical cattle slurry (6% dry matter), you can expect about 22-23 units of N/ac when applied using low-emission slurry spreading (LESS) methods.

Aim to spread slurry on dull damp days, and also spread on very low covers to avoid contamination of silage crop. If fields need to be rolled, roll early to avoid damaging grass. High-DMD silage fields would need to be grazed off and closed by early April for a May cut of silage. Pick your target cutting date and silage quality level needed and work back from that with grazing, closing up and fertiliser applications. Be careful with large applications of K fertiliser. Where over 70 units/ac is required, only 70 units/ac should be applied in spring with the remainder applied in autumn.

Turnout: Cattle continue to be turned out with a dry week helping ground conditions in many parts of the country. Herd closely for the first few days at grass. It can be a big change to go from a warm shed to a big open field.