Well it is a textbook. It is authoritative and boring to read unless you are into the subject. It has no pictures. It is a classic. Put it on the book shelf and pull it out to look stuff up on organic gardening. You know it will have the answer. Well most of the time - keep in mind if you are trying to find out about Neem oil for roses look in something more recent.
I have been a poor man's gardener for 40 years or so. Over the years I have accumulated dozens of books or booklets on gardening, yet I always end up looking up any subject in the Encyclopedia of Organic Gardening. It's the most useful book I have.