Green Farming    by Janice Daugharty
Price: $1.99 USD. 520 words. Published on October 7, 2010. .
Most things tagged free, I've found, are gonna cost you. Like the green fertilizer in this piece on green farming. Well, at least you can read about it for free...

A No-nonsense Guide to Growing your own Vegetables    by Paul Spivey
Price: $0.99 USD. 6720 words. Published on June 22, 2011. .
Food prices are soaring. This book will quickly bring you up-to-speed in a no-nonsense way on the topic of growing your own vegetables. I wanted to learn the ways my grandparents fed themselves and combine their wisdom with the advantages of today’s scientific advances. This book will give you the basics and provide lots of links where you can learn more, go much deeper.

Three Essays on the Environment    by R. H. Sheldon
Price: $0.99 USD. 4400 words. Published on September 18, 2011. .
The author takes a personal look at several environmental issues and how they impact us individually and as a whole.