my practice is to offer food twice a day (morning and evening) and remove the bowls after about half an hour, adjusting the quantity to suit how much was left/ how thoroughly the bowls were picked clean at the last meal, so is similar to BlindLemonChicken's. For most of the day the only food available is what they can find by foraging. Typically they forage in the morning and relax in the afternoon. They start shouting if I haven't put out the dinner by the time they think it should be provided
Then they graze the grass for a bit and go to bed.Late comers or would-be second helpers eat up anything that was spilled, unless they don't like it (in which case I chuck it on the lawn at dusk and the hedgehogs or whatnot typically consume it overnight). Rats are seen occasionally, but not such that they are a real problem: the chickens will chase them away unless they're so full that they don't mind sharing with rodents (it's the same with the wild birds like the local pheasants, robins etc). I also offer mealworms or other highly nutritious food to any bird that comes to the back door seeking it.
