The hedgerows are heavy with berries, the days are getting shorter, but what is the first official day of autumn in the UK in 2024?
With August on its way out, many gardeners are asking that perennial question, 'when does autumn start'? Whether you define the start of autumn as when the leaves starting to change colour, when the clocks go back or the dropping in soil temperature, we all notice it as a period of transition in our gardens – a time for tidying up, preparing for the first frosts and planting spring bulbs.
Marking the start of autumn by changes to the plants in our gardens is the phenological approach. But there are two other distinct definitions for the start of spring, the meteorological and the astronomical, which are determined by different factors.
When is the first day of autumn 2024?
What is meteorological autumn?
The meteorological start of autumn is marked by the first day of September every year. Changes in annual temperature determine when the meteorological seasons change, and the year is divided into four sections aligning with the Gregorian calendar. Under this system, autumn starts on 1 September and ends on 21 December.
What is astronomical autumn? And when is the autumn equinox?
Astronomical autumn is when the autumn equinox takes place. Equinox is Latin for 'equal nights' and it occurs when the sun is directly above the Equator, so day and night are almost of equal length all over the globe. The equinox takes place twice a year – once in March and once in September. This year the autumn equinox takes place on 22 September 2024.
What is the first day of autumn in gardening terms?
When it comes to your garden, it’s best not to get too hung up on dates and solar activity. Paying attention to the weather forecast and the average nighttime temperature will be the most important things when it comes to sowing spring bulbs and moving tender plants indoors. If you’re really keen to divide up the year then consider September to be early autumn, October to be mid autumn and November to be late autumn.
