Last weekends unexpected sunshine and high temperatures finally gave us that grass growth boost we were waiting for.

It is time to take advantage of this extra grass on farm and utilise it as much as possible because – according to Teagasc – 1kg of DM grass costs between €0.04 and €0.05, while 1kg of concentrates costs between €0.25 and €0.30.

To do this, we must match our feed demand to the grass growth rate. So, if growth is high – like this week (average growth 50kg DM/ha) – supplementation being fed needs to be reduced and grass intakes increased.

If growth is greater than demand, this will give you the opportunity increase your stocking rate and close up paddocks to be cut for bales. For grass quality, it is a good idea to try and alternate paddocks cut for bales.

To do this, you should keep and eye on pre-grazing yields. If paddocks begin to slip above a pre-grazing cover of 1,600kg DM/ha, this is a sure indication that you need to take out paddocks for bales.

The farm should also be walked regularly to identify any surpluses or deficits in good time. If you are grass measuring, the wedge will do this for you.

Grazing paddocks with too high of a cover will mean a reduction in quality, and therefore a reduction in milk yield. It will also affect your ability to reach the target mid-season post-grazing residual of 4-4.5cm.

A cover per cow of between 160-180kg DM/ha should be maintained and rotation length kept between 18-21 days throughout the mid-grazing season.

Grass Tetany

A sudden change in weather can leave cows susceptible to grass tetany. So, it is important to keep a watchful eye out, as if not caught in time, grass tetany can be detrimental for the animal.

Also Read: What to look out for and how to avoid grass tetany

Fertiliser

The target on the majority of farms is to have 100units/ac of Nitrogen (N) out by May 1. If you are planning on purchasing N fertiliser one option to consider – instead of CAN – is protected urea.

Protected urea is similarly priced to CAN and Teagasc trails have revealed that protected urea consistently yields as well as CAN in Irish grasslands – with no difference in annual production between the two fertilisers.

If you haven’t already done so, you should also consider spreading some sulfur (S), as N and S go hand-in-hand when it comes to maximising grass production and sward quality during the grazing season.

If you are applying 250kg/ha of N across the year, then 20kg/ha of S (16 units/ac) should be applied.