There's an old chicken coop at the back of my property. We decided to not have any chicken, but even if we wanted to we would have given them a new one.
Despite it being worn out it wasn't easy to tear down though. It was very sturdy. I kept the bottom of the tower where the chicken slept intact and turned it into a compost heap. Took out a window and used it to create a small greenhouse cabin to let seeds sprout under glass.
There was a very thick, almost concrete like crust on the bottom of the coop. A mixture of soil and chicken manure. It is devoid of all life. I covered it with shredded leaves and sticks from the hedges I took down. Hopefully something will be able to grow there next year!