I cought her by my house a few days ago, Is this a leghorn? how old do you think she is? can i expect eggs soon? I have a coop made for 4-5 layer hens shes really happy in, it has a nest box,roost, she uses everything but the nest boxes.
Scratch has no nutritional value, so don't feed her tons of it. Feed her mostly the layer. A good ration would be to mix it two scoops of layer to one of scratch. You can buy the big bags and mix it like this in a big metal trashcan. Its great for storage.
Keep her on layer and they don't need the scratch. It isn't a leghorn due to the white legs, but looks more like a game... are you sure it is female? Hard to tell from the pic but appears dubbed.