The days are getting shorter, temperatures are beginning to fall and, for many hens, the annual moult is just around the corner.
But depending where you live, September can still bring some surprisingly warm days.
So this month is about balancing the last of your summer care with preparing your flock, coop and run for autumn and the colder months ahead.
These 20 practical tasks will help you make that transition, from checking nest boxes and ventilation to planning ahead for moulting and winter.
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This article is written with the northern hemisphere in mind.
If you're in the southern hemisphere and dealing with more or less the opposite type of weather to this article, try using my tasks for whichever month comes closest to your season.
As your hens move towards the annual moult and egg production begins to slow, September is a good time to check that your nest boxes have worked well over the past laying season.
1. Check the position of your nest boxes.
Are your hens using them reliably, or have you had problems with eggs being laid elsewhere? Nest boxes should be in a quiet, sheltered part of the coop, away from draughts and direct light. If yours aren't working well, now is a good time to make changes.
Not sure what makes a good nest box? My guide to chicken nest boxes explains what hens need, and why.
2. Check the bedding.
Has it stayed reasonably clean and in place, or do your hens constantly kick it onto the floor? If your current bedding isn't working well, consider trying something different. Nest box liners can be a convenient, hygienic option.
3. Check carefully for mites.
Red mites particularly like cracks and crevices in wooden coops and nest boxes. Check regularly for signs of infestation and deal with any problem promptly.
My guide to red mites explains what to look for and what to do if you find them.
4. Give the nest boxes a thorough clean.
Remove old bedding and debris and replace it with fresh, dry nesting material.
It's a simple job, but heading into the wetter autumn months with clean, dry nest boxes gives you an excellent starting point.
I learned just how important nest-box privacy can be from one of my own hens.
She wasn't at all impressed with the arrangements I'd provided, and boy did she let me know it!
In this short video, you'll see what happened when she decided that she did not appreciate being disturbed.
It's a lovely reminder that however carefully we plan our coops, chickens will almost always have something to say about it!
Before the colder, wetter weather arrives, September is a good time to check your coop and deal with any small maintenance jobs.
Do them now and there'll be less to tackle when you give the coop its autumn deep clean.
Clear out ventilation to make sure it's ready for the winter.5. Check the ventilation.
Good ventilation is essential throughout the year, and particularly important in winter when moisture can build up inside a closed coop.
Make sure ventilation openings are clear of cobwebs, leaves and other debris. You need fresh air to circulate without creating a cold draught directly across your chickens while they're roosting.
6. Collect dry autumn leaves.
If you use the deep litter method, fallen leaves can be a useful free addition to your litter. Collect only clean, untreated leaves and make sure they're thoroughly dry before storing them. Damp leaves can quickly become mouldy.
Keep them somewhere dry until you need them, and avoid using them in nest boxes, where they're likely to be scratched and kicked out.
7. Check the outside of the coop.
Does any wood need painting, treating or repairing? September may offer some of the last reliably dry weather before autumn and winter set in, so deal with exterior maintenance while you still have a suitable spell of weather.
8. Check locks, latches and weak points.
Make sure doors close securely, latches work properly and there are no new gaps or damaged areas a predator could exploit.
Don't rely on a simple sliding bolt if a clever predator could open it. A secure coop should require more than one simple movement to release the latch.
Trees and shrubs can make a valuable addition to a chicken run. They provide shade, shelter and places to explore. Choose fruiting varieties and your flock may get an occasional seasonal treat, too!
September can be a good time to start planning what to plant, although the best planting time will depend on your local climate.
9. Find out what grows well in your area.
Look at which fruit trees and shrubs thrive in neighbouring gardens, and ask a good local nursery or experienced gardener for advice. Not every variety will suit every climate or soil.
10. Consider an apple tree.
Dwarf varieties can work particularly well where space is limited, and once established the tree will provide valuable shade as well as fruit.
Chickens can eat apple flesh, but the seeds contain amygdalin, which can release cyanide when digested. There's no need to panic about the occasional windfall, but I wouldn't deliberately feed apple seeds to your flock. Remove the seeds when offering apples as a treat.
My guide to feeding apples to chickens has more information.
11. Think beyond fruit.
The most useful planting doesn't necessarily have to produce something for your chickens to eat. A well-chosen tree or shrub can provide shade in summer, shelter from wind and rain in colder months, and a more interesting environment for your flock.
Choose non-toxic plants that are suitable for your local conditions and, particularly in smaller runs, check their eventual height and spread before planting.
12. Choose fruit trees and bushes carefully.
Depending on your climate and available space, possibilities include pear, fig, plum and other locally suitable fruit trees, together with berry-producing shrubs.
Remember that chickens can be surprisingly destructive gardeners! Protect young plants and their roots until they're well established, and check whether a species is invasive in your area before planting it.
Windfall apples can provide an occasional treat — and plenty of interesting bugs to investigate!As daylight hours shorten, many chickens will begin their annual moult. Growing a new set of feathers requires plenty of good-quality protein, so September is a useful time to think about your flock's nutrition.
A good-quality, nutritionally balanced chicken feed should remain the basis of their diet. There's no need to overload your hens with high-protein treats, but once moulting begins you can offer small amounts of suitable protein-rich foods alongside their normal feed.
13. Learn to recognise the signs of moulting.
Feathers around the head and neck often begin to disappear first, egg production may slow or stop, and your hens can look surprisingly scruffy!
My guide to moulting chickens explains what to expect and how you can help your flock through it.
14. Check your chickens' main feed.
Make sure they're eating a good-quality, nutritionally balanced feed appropriate for their age and stage of life. During the moult, treats should remain just that, rather than replacing their normal ration.
15. Plan some healthy protein-rich extras.
If you want to supplement your flock's diet while they're growing new feathers, choose appropriate foods and offer them in moderation.
I've put together a guide to protein-rich foods for chickens, including sensible options for the moulting season.
16. Try fermenting some of their regular feed.
Fermenting doesn't turn chicken feed into a high-protein food, but it can be an interesting way to offer their normal ration and may have nutritional benefits.
If you've never tried it, my step-by-step guide to fermenting chicken feed explains how.
17. Make the most of seasonal garden produce.
If you have a glut of ripe tomatoes, your chickens can enjoy small amounts as a treat.
Ripe tomatoes are safe for chickens, but keep the green parts of the plant, including leaves and stems, away from your flock. And remember that tomatoes, like other treats, shouldn't displace their nutritionally balanced feed.
13. During the last week of the month, begin making some fermented feed. Find out about the benefits of fermenting here.
14. How to ferment chicken feed: this article walks you through four simple steps to fermenting food for your flock, from choosing the right container to exactly what to do.
Ripe tomatoes can be an occasional treat, but keep chickens away from the leaves and stems.After the dry days of summer, it's easy to forget just how quickly a chicken run can become wet and muddy once autumn rain arrives. September is a good time to spot potential problems and deal with them before the weather deteriorates.
18. Check the run for drainage problems.
Think back to last winter. Where did water collect? Which areas became particularly muddy?
If possible, improve drainage or deal with low spots now, before persistent rain makes the job much harder. My guide to the best flooring for chicken runs looks at different options for keeping a run usable in wet weather.
19. Make sure your flock has somewhere dry outdoors.
Chickens need protection from prolonged rain as well as somewhere to shelter from strong winds.
Check that any covered part of the run is still watertight and secure. If your run has little natural protection, consider adding a weatherproof cover over part of it while making sure the area remains well ventilated.
20. Check the run for autumn hazards.
Walk around the run and look for anything that could cause problems as the weather changes: damaged fencing, loose wire, unstable branches, blocked drainage or vegetation that has grown through or weakened the boundaries.
It's also a good opportunity to clear away accumulated debris and make sure gates and fencing are secure before winter weather arrives.
September is a month of transition for your flock. A few simple checks now can make the move into autumn much easier.
Don't feel you have to tackle all 20 tasks at once. Work through the ones that are most relevant to your flock, your climate and your setup.
And if your hens begin looking decidedly scruffy as the month progresses, don't panic! The annual moult may well be underway. My guide to moulting chickens explains what to expect and how to help them through it.
I'll be back next month with the October checklist and another set of seasonal jobs.
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A lot of "facts" you'll find on the internet are often people's individual views, based on inaccurate information repeated from poor quality sources.
The information I provide in this article and others is based not just on my own experience, but on evidenced facts from scientific, peer-reviewed research and books from highly respected and experienced poultry keepers such as Gail Damerow.
Some of the trusted sources I have used in this article are these.
1. Woodland Trust: Tree Planting for Free Range Poultry. Pub. Woodland Trust, 2014.
2. Woodland Trust: Enhanced bird health results in premium woodland produce. Pub. Woodland Trust, 2016.