There are two dates autumn can start in the UK, depending on whether you’re looking at the astronomical or the meteorological calendar
But for those of us who aren’t built for the heat, autumn can’t come soon enough – cooler temperatures, changing leaves and darker nights are all signs that the season is about to start in the UK.
But when exactly does autumn 2022 begin? The answer is more complicated than expected.
When does autumn start?
According to the Met Office, there are two distinct dates that can mark the start of the season on our calendars.
One is defined using the Earth’s axis and orbit around the Sun, the other is a fixed datum used by meteorologists.
The Met Office says: “When we speak of the first day of autumn, we are usually referring to the astronomical autumn defined by the Earth’s axis and orbit around the Sun.”
This year, according to the astronomical calendar, autumn begins on Friday, September 23, 2022 and ends on Wednesday, December 21, 2022.
However, according to the meteorological seasons, the first day of autumn begins on September 1st and ends on November 30th.
Meteorological seasons are based on the annual temperature cycle and coincide with the calendar to divide the year into four periods of three months each.
The Met Office says: “These seasons are split to coincide with our Gregorian calendar, making it easier for meteorological observations and forecasts to compare seasonal and monthly statistics.”
Using meteorological seasons, the season is defined as:
- Spring (March, April, May)
- Summer (June, July, August)
- Autumn (September, October, November)
- Winter (December, January, February)
What is the Autumnal Equinox?
The autumnal equinox in the northern hemisphere marks the end of summer and the beginning of autumn.
Every year there are two equinoxes, spring and autumn, and two solstices, summer and winter.
On the autumnal equinox, day and night are roughly equal in length, according to the Met Office.
From that day onwards, however, nights will progressively become longer than days until the vernal equinox in March, when the pattern reverses.
At this time of year, the northern hemisphere begins to tilt away from the sun, resulting in less direct sunlight. This is why temperatures start to cool at this time of year and we get more moody lighting in the autumn months.
Due to the Earth’s elliptical orbit around the Sun, the dates of the equinoxes and solstices are not fixed.
What are some signs of autumn?
There are a number of signs that fall has arrived. That Woodland Trust recommends paying attention to the following:
- Leaves change color – One of the prettiest signs of fall are the leaves changing from green to red and orange. This change is caused by the cooler temperatures and shorter days, which means less sunlight.
- migratory birds – Birds such as nightingales, cuckoos, swifts and swallows fly south in search of warmer temperatures to await the colder seasons. You’ll also see some new arrivals including redwings, fieldfares, waxwings and species of ducks and geese making their home in the UK from colder climates like Iceland and Sweden.
- Conkers and Acorns – In autumn, many trees ripen and fall to the ground, so keep an eye out for acorns and chestnuts on sidewalks and paths.
Which flowers are best planted in autumn?
Just because we’re entering fall doesn’t mean avid gardeners have to go without their beloved plants and flowers until the warmer months return.
- Cyclamen persicum will produce some amazing blooms by the time the first hard frosts begin, and will bloom well into winter in more sheltered environments
- With its leaves, the purple sage is an ideal “ornamental plant” that cuts a fine figure at any time of the year
- Nandina domestica will fill your garden with color all year round – in summer you can expect yellow-green leaves, and as the weather cools its leaves turn a bright red
- Ceratostigma plumbaginoides can bloom its incredible flowers for weeks in September and October in a sunny spot
- Winter pansies also offer reliable color from fall to mid-spring