The Bureau of Meteorology has declared that a third La Nina event is underway. Key atmospheric and oceanic indicators now show an established La Nina. This is likely to peak during spring and return to neutral early in 2023. Since 1900 there have been 20 La Nina events and only three times have there been three in a row.
Above average rainfall is expected for northern and eastern parts of Australia during spring and summer. Rainfall for September was 150mm compared to the monthly mean of 88.6mm. Daylesford is well on the way to achieving its median annual rainfall of 874mm with 864mm to the end of September. Daytime temperatures are likely to be a little cooler than average and warmer than average at night.
Water storages across Australia continue to fill and Melbourne’s reservoirs, at around 94.5%, are over 11% more full than at this time last year. Many farming areas would have appreciated good winter rains but now are likely to be concerned about too much rain affecting their crops.
Spring brings changes with plants and animals. We are starting to see some birds coming here that had taken vacations to warmer climates during our cold, wet winter. Skinks have started to get active in our gardens on milder days.
While it is still cold and wet, many types of weeds are growing quickly before the more welcome plants take off. It is a good time to prepare your garden for spring and summer vegetable crops. Tomato seedlings are already available locally, however it is still too cold to plant them in the ground as they can be decimated by frost. If you have a greenhouse, an option is to re-pot tomato seedlings into a bigger pot and also deeper into the soil. Tomato plants will shoot out extra roots above their initial roots if planted a bit deeper and this can help to make them more robust. Local advice is not to plant tomatoes before Cup Day because of the cold nights and potential for frost. If you are keen to plant during October, you should ensure that the plants are protected against the cold and frost. Moveable mini-greenhouses can provide protection and better temperature control for sensitive plants.
The Bureau provides a vast range of information including Root Zone Soil Moisture across Australia. Currently, most of Victoria has Average or Above Average RZSM. Large parts of the continent have Above Average or Very Much Above Average RZSM for this time of the year.
Victor Szwed is a Daylesford resident who contributes a regular weather update to The Wombat Post.