I am new to back yard chickens and I am loving every minute of it! But, I bought four hens that were 6 months old and they were laying. I have had them 4 weeks and there are no eggs to be seen. I put nesting boxes in and have straw in them and plastic eggs but still no luck. I am feeding cracked corn, laying pellet and oyster shells. They can go outside in their pen any time and back inside. They are bantam cochins and Polish Top Hats. What am I doing wrong ??? I love these beautiful birds! I also have 15 silkies and 8 cochins in the incubator that are due to hatch March 1st. I think I have the fever! Thanks for any information!