When is the right time to get your autumn pastures sown?
This is a common question and discussion point at this time of the year, especially once the weather starts to cool.
So what is the answer?
Firstly, there is no silver bullet — sorry to disappoint!
Sowing date will depend on the forage type you’re working with, your region and your climate.
Sowing to a soil temperature will give the best result, not a calendar date (although, for rye-grass, after St Patrick’s Day seems to be popular).
Rye-grass needs a soil temperature of less than 25°C to germinate. To measure this, you can either invest in a soil thermometer or use the air temperature as an indicator.
For rye-grass we want an average daily temperature less than 25°C for seven to 10 consecutive days. Cereals, on the other hand, want a daily temperature of less than 20°C for the same period.
Sowing too early and getting some hot temperatures (mixed with hot, exposed water due to irrigating prior to any plant canopy build-up) on freshly germinated plants is a recipe for failure.
Although early sowing can result in extra feed available to cows (assuming growing conditions are right) — which is a big plus for freshly calved cows — if the timing is wrong then there is the risk of having to resow pastures, which is an added cost in an already tight cashflow year.
So as mentioned at the start, there is no silver bullet. Sowing to temperature will give you a better chance to get your autumn pastures up and away.
There is plenty of hay and or silage around this year that can be used to fill cows up to help protect the fresh pasture.
Very early sowing can increase autumn yield (if conditions are suitable), but there is a large risk of significantly reduced germination due to conditions being too hot. Be aware that a cool February does not necessarily mean a cool March, as many may remember from 2016.
■ For further information please check the Murray Dairy website http://murraydairy.com.au/LiteratureRetrieve.aspx?ID=153141 and speak to your agronomist for the best sowing program for your farm business.
— Lisa Birrell, Murray Dairy