In a large bowl, mix together 1 cup of the all-purpose flour, the whole wheat flour, oats, yeast, and salt.
Stir in butter and honey and mix well.
Add the water and stir to fully incorporate all ingredients.
Add remaining all purpose flour 1/2 cup at a time, until you have a shaggy, cohesive dough that pulls away from the sides of the bowl (you may not use all the flour).
Generously flour a work surface and dump out your dough. Keeping your hands and the work surface floured, knead dough until you have a smooth ball of dough that springs back when gently pressed with a finger. Be sure to scrape up and discard any stuck bits of dough - you don't want to incorporate them back into the dough.
Place dough in a large greased bowl and cover with a kitchen towel or plastic wrap. Let rise for 1 1/2 hours.
When dough has risen, dump out onto a floured surface and gently press to remove excess air. Form into a loaf shape and place into a greased 9x5 pan.