So why aren't all the eggs green?
		
		
	 
Maybe blue is recessive?
		
 
		
	 
not at all!
In chickens  there  is only 2 egg shell  color white  and blue. 
The brown  is anoter featcher  that chicken that have it smire a brown color, protoporphyrin which is derived from hemoglobin on the egg shell. 
If the egg is  white you will recive a brown egg
If the egg  is blue  you will recive a GREEN egg.
Every Genetic trait is determined  by at least 2 gene.
In chicken  the white gene ( lets call it -w ) is recessive  to the gene that produce the oocianin ( let call it -W) which  give the blue  color. And the there is anoter separate  gene that give the brown  coating. 
So what posability we have
ww- white
WW -blue
Ww- blue
ww + brown gene= brown egg
Ww+brown gene= green egg
WW + brown gene= green egg
If you cross 2 green  eggers it depends on the combination of gene in the parants
If the parents  are
WW ×WW the 2 with  the B gene all the hens will  lay green
If the parents are
WW×Ww withe Brown  gene all the hens will lay green
BUT
IF THE PARENTS  ARE 
Ww x Ww + the brown  gene
You will have hens thay will lay  Green eggs ( WW and the Ww combination  with  tge brown gene)
And some  will lay Brown  eggs ( ww + brown egg combination)
Uffff that was hard!