So, the reason why Spring in Australia starts on the first of September is due to an army rule dating back to the start of the Australian colony, early 1800’s. At the time there were two uniform’s standards, the winter and the summer one. The change over, for all troops, was on the first day of September and the first day of March, therefore Spring and Autumn.
This seasonal change is still practiced in many schools across the continent.
Similar set of strange rules abound all over the world, to define what spring is, and indeed if Spring is something we should talk about at all.
Below is how the spring season is lived around the world from the wikipedia entry on the subject:
In the USA and some other regions in the Northern Hemisphere, the astronomical vernal equinox (currently around the 20th or 21st of March) is often taken to mark the first day of spring, and the summer solstice is sometimes taken as the first day of summer (usually 21 June in the Northern Hemisphere). In South Africa, Australia, and New Zealand, spring begins on 1 September, and has no relation to the vernal equinox. In Ireland spring traditionally starts on 1 February, St Brigid’s Day.
In South America, the Tupi-Guarani calendar, from the former inhabitants of what is presently Brazil, Northern Argentina and Paraguay, counted 365 days, plus a fourth part of a day, needing no extra day every four years. The beginning of the solar year was marked by the rising of the M25 Constellation in the horizon, which occurs between June 5 and June 11 in this part of the world. For these native peoples, the four seasons were clearly identified by the solstices and equinoxes. The trajectory of the Sun throughout the year was divided into “The New Age” (Ara Pyau) and “The Old Age” (Ara Ymã). Ara Pyau was spring and summer, and Ara Ymã was autumn and winter. This calendar, which had no graphed or written form, marked activities such as hunting, fishing, planting, harvesting and religious rituals.
In East Asian Solar term, spring begins on 4 February and ends on 5 May. Similarly, according to the Celtic tradition, which is based solely on daylight and the strength of the noon sun, spring begins in early February (near Imbolc or Candlemas) and continues until early May (Beltane).
Swedish meteorologists define the beginning of spring as the first occasion on which the average daytime temperature exceeds zero degrees Celsius for seven consecutive days, thus the date varies with latitude and elevation.
The phenological definition of spring relates to indicators, the blossoming of a range of plant species, and the activities of animals, or the special smell of soil that has reached the temperature for micro flora to flourish. It therefore varies according to the climate and according to the specific weather of a particular year.
So, on top of this we should add another layer to make it Australian specific: seasonal calendar based on traditional knowledge of the environment.
Below is a diagram adapted from Flood, 1980 by Daphne Nash. See Halling, 1999: 41, as found on the resources available at the Australian National Botanic Gardens website.
The diagram relates to the surviving knowledge of the Aboriginal people that lived in the NSW Southern Tablelands and ACT region.