We cleaned the chicken pen today. The first time ever. We have 10 boxes and 6 hens. Our box isn't very big but it took quite a while... what a job! We filled a 50 lb horse feed sack full of chicken manure. We took it and put it all round our tomatoes, A&M jalepeno's, green beans and all of our front yard flowers... Anyway....So, how often should a chicken pen be cleaned out? We put fresh hay in the boxes and almost before we could get the last board nailed in Hatty was in the box laying an egg!