Just when farms were beginning to dry out and grass was starting to suffer from distress caused by a lack of moisture, the weather duly obliged with heavy showers over most of the country over the past few days.

The range in rainfall is between 10mm and 40mm in the seven days up to last Saturday, but more rain on Sunday and Monday morning will have helped farms that were getting dry.

This will boost grass growth, especially on dry farms. Average growth rates for the past seven days were about 60kg per day, which is more or less equal to demand on most farms. After this rain, we can expect growth rates to increase again to the mid to high 70s, depending on when nitrogen was spread.

The forecast for the week ahead is for the showery weather to continue.

Ideal weather

Decisions about how much fertiliser to spread should be based on how much grass is on the farm and how much grass you need to grow over the next month.

This is determined by the stocking rate and how much silage you have. In these weather conditions, urea is the fertiliser of choice as it is cheaper per unit of nitrogen than CAN and very little volatilisation will occur in damp conditions like we have today.

Don’t forget to discount the value of nitrogen in slurry. This is ideal weather for spreading slurry after silage. For every 1,000 gallons of slurry per acre, there is the equivalent of 6.5 units of nitrogen, five units of phosphorus and 30 units of potash.

If blanket-spreading nitrogen, be wary of spreading too much of the farm at once though, as this may restrict you in what paddocks you can cut for silage, if surplus grass appears. The last thing you want to be doing is waiting to cut paddocks for silage because, as we know, grass growth can change quickly at this time of year so as much of the farm as possible should be available for grazing.

Monday management: ideal weather for spreading slurry after silage

Widespread and sometimes heavy rain across the country over the last few days has boosted grass growth.