An allotment is a very good place to keep chickens as you will be able to grow a ready supply of greens to feed them. We give them over-size courgettes, brussell sprout tops, bolting lettuce etc.
We feed our chickens a diet of layers pellets and they also get a few handfuls of mixed corn each day. They need access to grit as well. Sometimes when I have used a lot of eggs, I feed the egg shells back to them.
Our chickens are in a fixed, but very large, pen and we have used a shed for their coop. Building the walk in run was quite a large job but it keeps them safe and gives them a large area. We have added extra outdoor perches.
Our hens have come from a variety of sources, some from poultry auctions, some from local sellers - look in your local paper. We have chosen different breeds that give us a variety of egg colours. We have Leghorns for white eggs, cream legbars for blue eggs, marans for dark brown eggs to name a few. We have found the Amber link hens particularly friendly.
We use bales of wood shavings from our local farm suppliers in the coop with straw for the nest boxes. We do a full clean once a week, or more frequently if needed. The old bedding goes into the compost bin and makes fantastic compost for the allotment.
We visit the chickens every day, but do not lock them away at night in their coop. They are secure in their fully enclosed run and we have built a porch in front of the coop entrance to protect them from the elements. We check their feed and water daily. We have purchased large galvanised feeders and drinkers and have found these well worth the investment.
The rat population has been persistant this year and we have had to take measures to keep them under control.
We have thoroughly enjoyed keeping chickens, although it can be a big time commitment to visit them daily, particularly when the days are short in the winter. It has probably cost us more than I would like to add up, by the time you factor in the housing/bedding/feeders etc.
We have enlisted the help of a fellow allotment holder, who will see to the chickens on any days we can get up there, in return for as many eggs as he would like!