Maize and Wheat

You'd be best sticking to layers pellets in my opinion.  They have all that the hen needs but maize and wheat are mainly carbohydrates so you'll need to feed other things as well.  Maize and wheat will make them fat and that's not good

If you do that they will just pick out the maize and wheat and ignore the pellets. Maize and wheat really should only be given as a treat every now and then (daily in winter and not so necessary in summer if your hens are free ranging) or you will end up with fat non laying hens 

Mine get pellets with treats of mixed grain in the evening  as a treat (if they have been good) and seem happy with that.