In the simplest terms, if a group of chickens strip a garden then they don't have enough room, or enough plant diverstiy.
Exactly. That's it in a nutshell.
It can be done with less than an acre but it requires a lot of thought
Yes, a lot of thought. But it does not require a lot of maintenance; in fact, the opposite. I do far less now than I did when I had a 'normal' garden without chickens wandering about in it.
The diversity and quantity of forage increases when people STOP interfering in what happens all by itself out there. Chickens are looking for fauna to eat, far more than flora or funga. The sort of fauna they're after like *undisturbed* ground, *rotting* plant material (leaves, twigs, branches, logs, roots), other minifauna to parasitize and eat.
What I had to learn to do was to let go. Stop tidying up. Stop cutting off (and disposing of elsewhere) dead bits etc. So now I only do that where it shows, and everywhere else is essentially let go, to 'rewild' all on its own, and I intervene only when necessary to limit the thugs like bracken and brambles, and as required to keep access open for me. I have a bonfire only when the pile of stuff that has to be burnt takes up too much space on the drive; until then, it is a popular foraging spot because of all the minibugs that love dead plant material. It's untidy, but so is nature.
A well planned shrub border, that you like to look at year round, and that provides cover for the chickens, and attracts pollinators (so, generally, something with scent, because wind-pollinated plants don't need to bother to attract insects) does a lot for everyone with very little ongoing maintenance. There is a multiplier effect. Like with the scent - a win-win for the gardener and chickens - a low maintenance border means undisturbed soil, lots of detritus (because fallen flowers, leaves and twigs are just left where they fall, mostly out of sight under the shrubs) and lots of quality forage for chickens. By me doing essentially nothing once it's planned and grown. It's the same as big and untidy hedges supporting far more birds than neat homogenous hedges.
And the more fauna, flora and funga that lives in any square metre, the less square metres are needed to sustain a chicken. I have about 30 birds in a little over an acre. Of course they do wander up the lane and occasionally into neighbours' gardens, so all measures need to be considered 'rough and ready'
A group of dawn to dusk free ranging chickens, or true free rangers will set their own boundries.
It is influenced by how much, and how much they like, what they are offered to eat by the keeper. Mine went into neighbours' gardens more often before I got the fermented feed mix properly suited to their needs, and when I offered them less food at breakfast.
This is key. And the best way to increase this is to let the stuff that just appears in the garden stay. What we call weeds are the plants that are local and thrive in that location. And because they are that, they will each support an array of local minibugs and funga, which in turn will support other fauna, funga and flora. Webs of life and all that. Leave the weeds where you can (though controlling the thugs) and lots of other life will just appear, as if by magic, in your garden. A few untouched quiet corners will continually reseed the rest of it, so you don't have to have wild and untidy on show everywhere.
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