The Autumn Break is an annual event that usually occurs sometime between late March and early May, here on the Mornington Peninsula. It is defined as being either 25mm of rain in one day, or 30mm of rain over one week, in the lead up to winter and the rainy season.
Essentially, it is the first good rainfall before winter really kicks off, and is needed to get the initial crop or pasture growth going out in the paddocks. The timing of this rain event (coupled with paddock sowing) is actually incredibly important. Too early and there is the chance of a dry spell occurring afterwards that may kill all the newly germinated seeds. Too late, and retained soil warmth from summer and early autumn will have decreased to the point that seed germination is substantially slowed, leading to reduced productivity.
For us here on the Mornington Peninsula, the Autumn Break arrived in early April. There had been some localised heavy falls during March, however hot dry spells after these actually killed off much of the germination that occurred following the initial March rains. The rainfall that we had in April however, was sustained and whilst there was some warmer weather afterwards, it was not hot or dry enough to completely deny the newly germinated seedlings the water they required to continue their growth. In fact, those last few weeks of warmer weather helped to maintain a slightly higher soil temperature, thus providing the perfect growing conditions of optimum moisture and warmth for good pasture growth.
You may have noticed that paddock growth has now started to slow – temperatures have dropped significantly this month, and with some areas experiencing water logging, neither of these situations are ideal for plant growth. Enzymes are required by every biological system in order for life to occur – if the surrounding conditions (including temperature and water availability) change to something outside the optimum range, enzyme activity will slow – thus plant growth will also slow. If you had planned a sowing event this season, it might now be best to wait for the weather to warm up.
The Autumn Break is unpredictable, but something that many farmers do rely on to kickstart their winter crops and pasture. Having a good understanding of this event and its importance to farming is imperative if you are wanting to implement and maintain sustainable farming and effective cost management on your farm.
Cheers and happy farming!
Chris
