Does Fall Always Start On The Same Day? (Autumn Facts)

I love the fall. The color of the leaves and those misty mornings – it’s a beautiful time of year. But does it always arrive on the same day?

The first day of fall varies yearly, but normally only by a few hours. It’s usually on 22 or 23 September, and occasionally on September 21 or 24. However, the date also varies based on the astronomical fall determined by the equinox, and the meteorological fall based on the Gregorian calendar.

I’m getting a bit confused – so let’s clear all this up by looking at the start dates of fall in more detail in the rest of the article…

Does Fall Always Start On The Same Day?

Is The First Day of Fall Always On The Same Day?

The first day of fall varies from year to year, but normally only by a few hours. It’s usually on 22 or 23 September, and occasionally (but rarely) on September 21 or 24. We’ll look at why this is in a moment.

But, the answer isn’t quite as simple as that. The September date we’re talking about here is astronomical fall, which is determined by the equinox. There’s also meteorological fall, which does start on the same day each year, 1 September. Meteorological fall is based on the Gregorian calendar, which divides the seasons into neat, three-month chunks.

So, in answer to the original question, no and yes!

What Determines The First Day of Fall?

The first day of meteorological fall is determined by the autumnal equinox, which is why it varies slightly. The autumnal equinox is the first day of fall in the northern hemisphere (and if you live in the southern hemisphere, it’s the spring equinox). The equinox occurs at the same moment, wherever you are in the world.

What exactly is the equinox? Imagine that the equator reaches up into space. That’s the “celestial equator”, and the equinox occurs when the center of the sun passes across this line. The term equinox literally means “equal night”, so this marks the time twice a year when the day and the night are the same length.

Because the equinox is defined by the position of the sun and moon at a specific moment, it varies slightly from year to year, which is why the first day of fall can be on the 22nd or 23rd of September. Every few thousand years, it lands on the 21st or 24th. 

Are Day & Night Equal At The Fall Equinox?

The name equi (equal) and nox (night) suggests that day and night are exactly the same length on the fall equinox. The truth is, they’re only roughly equal, but as they’re unequal by just a matter of minutes, we don’t think anyone’s going to argue to have “equinox” renamed!

This short film from National Geographic explains the fall equinox really well.

What’s The Difference Between The Autumn & Spring Equinox?

The spring equinox (also called the vernal equinox) is the first equinox of the calendar year, and occurs on the 19th, 20th, or 21st of March. Like the autumnal equinox, this spring equinox is the moment when the center of the sun intersects with the imaginary celestial equator line.

As with the fall equinox, the length of the day and the night are roughly the same at this point. Then gradually, the days begin to lengthen as we move towards 21st June. In the southern hemisphere, the March equinox is the autumn equinox and marks the days starting to become shorter.

What Happens in The Garden in The Fall?

As the fall equinox is happening up there in the celestial equator, there’s plenty happening down here in your yard, too. The start of fall sees changes occurring in our gardens, with the leaves starting to turn and drop, summertime flowers fading while late summer plants come into bloom, and hopefully, you’ll also have a good harvest of those crops you’ve been tending for weeks.

Of course, the United States is a big place, and fall means something quite different depending on where you live. If you’re in Florida, you’ll notice very little difference as the first if September passes: it’ll still be hot. In more northerly states, September marks the time when you need to start preparing for the long winter ahead.

If you’re new to yard work, get to know which plant hardiness zone you live in. The US is separated into different gardening regions (or “hardiness zones” as they’re called), based on the typical climate and temperature. Knowing which zone you live in will give you a good idea what to expect in the fall, and to plan your garden accordingly.

Find out which plant hardiness zone you live in by typing your zip code into the USDA plant hardiness zone map. When you know this, it’s much easier to research what can and can’t be planted or harvested in the fall.

In general, you can expect the leaves to change color and fall from the trees, and this generally marks the time when gardening becomes less about growing, and more about clearing up. Let’s take a closer look at good jobs to do in your yard in the fall.

Autumn tree and sunshine

Summary: What Jobs Can We Do in The Yard in the Autumn?

Assuming you live in a daily moderate climate, the fall is about tidying up after the summer, and getting your garden ready for the winter. There are a few really important jobs to fit in between the summer and the colder weather.

A really good job to do in the fall is to winterize your lawn, by mowing, aerating, and feeding it. However, this varies depending on whether you live in a hot or cool climate, so take a look at our article about winterizing lawns before you embark on this.

The fall is also the best time to plant trees in your yard, especially fruit trees and deciduous trees. At Take A Yard, we follow the old saying about not planting trees until the leaves start to fall. Why is this? Trees are sensitive plants, and they don’t care to be uprooted before they’re dormant. By the fall, they’ve stopped producing fruit and leaves and are settling down to a winter’s rest.

The soil is also good for tree planting in the fall. It’s warm and loose, and sits perfectly between the too-hot earth of the height of summer and the solid ground of winter. This makes it the perfect time for the tree’s root system to establish itself. This lovely, loose soil is also great for bulbs; so plan ahead, and get your daffodil and tulip bulbs in the ground before the first frost.

We take you through what you can and can’t plant in the fall in our series of articles: What Can You Plant in September, What Can You Plant in October, and What Can You Plant in November. The answer to these questions is actually, a surprising amount, if you’re willing to be creative and adapt a bit.

These articles go into more detail about fall planting, month at a time. However, in general, we’d suggest making sure your lawn is healthy, your soil is tilled, and any fall planting (such as fruit trees and bulbs) takes place before that first frost. Knowing when the first freeze occurs is a key piece of information for any fall gardening task.

A few useful yard maintenance jobs for the fall include:

  • Fix anything that needs repairing before the winter, such as gutters, gates, and window catches
  • Carry out any last-minute painting jobs – before decorating your yard for the holidays!
  • Clear out and organize your shed or garage (kind of the opposite to a spring clean)
  • Do any plants need covering or moving indoors?
  • Winterize your patio furniture, your grill and any outdoor cooking equipment
  • Have a plan ready for your outdoor faucet and pipes, in case it freezes in the winter
  • Harvest your veg before the frosts. You may need to get batch cooking, freezing, or pickling, too
  • Set up a compost pile for all those swept-up leaves
  • Does anything need tying down or putting away before the weather turns?

Whatever jobs you end up doing in the garden next fall – I hope you enjoy autumn as much as I do.

The famous poet John Keats called it the ‘Season of mists and mellow fruitfulness’ – and I think this sums it up beautifully. 🙂