A writer is not worth their salt if they are not a reader as well. I have met many writers who can not give me a name of an author they like and some even have long explanations as to why they don't read. I have heard it all. One amateur told me they don't read and nor do they derive inspiration from music or art work. They told me they just let it flow and after she told me this I realized that was most likely the reason why her vocabulary was so limited and her writing elementary.
A writer can not get better at their craft if they do not study the masters.
A historical writer can not create an accurate historical world without research. For the overall amount of time I spend on my book, average about 15 to 20 hours a week, half is spent writing or editing. The other half is spent reading either fiction, mainly historical mysteries at the moment, or non-fiction books like the one I just got at the library and just can't put down.
Poison, An Illustrated History by Joel Levy.
This book is very heavy on science and terminology, which is not normally what I go for but the subject matter is so intriguing and I am reading it with my notebook at the ready to jot down facts as I read them or even plot lines that occur off the cuff as well.
These kinds of books, historical non-fiction, have fulfilled a need within me to find out as much as I can and also provides a three dimensional aspect to my books. I doubt I will ever stop devouring historical non-fictions because I will never learn it all. I will forever be a student of the past.