Fertilising second-cut silage as soon as possible

With many farmers having cut their first-cut silage over the weekend or planning on cutting in the next number of days, the focus will turn to fertilising second cut silage as soon as possible.

A good second-cut silage crop is vital to build a good silage reserve for a potentially long winter ahead.

Teagasc research has shown that there is a high grass growth rate response to nitrogen (N), in second-cut silage.

N will push grass growth and yield, but, it is important to get N application right to drive the growth, while making sure you are only applying what is required.

To further maximise your crop, a balanced nutrient supply is vital, along with appropriate applications of phosphorus (P) and potassium (K).

Requirements for fertilising second cut

Your second-cut silage should be fertilised according to the crop yield potential.

The table below is a fertiliser requirement provided by Teagasc and is based on a grass dry matter (DM) yield of 2t of DM/ha to four t DM/ha, which is the equivalent to three bales/ac and 6.5 bales/ac.

N, P and K requirements for second cut:

Protected urea can also be used and can replace CAN as a N source and your cattle slurry should be spread in, ideally, damp and overcast conditions.

The value of this cattle slurry with a 7% DM, when using low emission slurry spreading (LESS), is six units of N, 5 units of P, and 32 units of K for every 1,000gal.

For second cut, it is also important to include sulphur (S) in your application, as it is linked to N uptake and N use efficiency (NUE) as the response to S increases with the rate of N applied.

Not applying S can have a negative impact on your silage quality as low protein silages is the result of a lack of S in the grass.

With all of this in mind, fertilising and slurry application should be done as soon as possible after first cut to try and have your second ready for mid to late July.