Chickens in winter

So it's not winter exactly, but the garden is behaving as if it were, and so are the chickens, to be honest.  The trees are mostly bare (leaves are great fun to scratch up);  the lawn is also mostly bare (grass is yummy, but why won't it grow back?).  Yesterday morning we had a hard frost;  the six year old went out in the morning with a hot kettle to melt all the chicken drinks (he thought it was the best thing ever).  When it snowed early this month, the chickens were very confused:  what was it, and where did the grass go?

The more pressing chicken/winter concern is the distinct lack of eggs.  We've dropped from 8-9 a day to around 4-5 a day.  Actually, we suspect one or more hens may be hiding a nest from us;  Rock, our newest laying hen with a distinct blue egg, hasn't laid one in the nest box for at least a week.  We think she's too young to go off her lay, so she must be hiding them.  We also suspect Cookie, the same age as Rock, is also hiding a nest, as she's about 7 months old and well past time to begin laying (we've never had an egg from her yet, and Rock's been laying for a couple months now).  We've all been out to have a look for eggs, but no luck yet. We don't even know what color Cookie's eggs will be, just that they'll be small (she's a Pekin bantam).

It's not as fun in winter for chickens as it is in summer:  less greenery to eat, fewer bugs.  It's cold and wet.  I recently saw a chicken attempt to have a dustbath in the mud (at least there are fewer pests, too).  We still rotate them around the garden, but there are a couple of no-go areas at the present, including the lawn.  They've eaten the grass down almost bare, and will have to wait for it to grow back a bit;  instead of having lawn 3 weeks out of 4, they'll probably have to go 3 or 4 weeks off before the first section can take their scratching and pecking.