Decoupage is a decorative technique in which a design is made of pieces of printed paper which is then glued onto a base, furniture, wall, or some other flat medium and varnished.
Regular Blogs
Split about equally between decoupage and gardening, this blog's author writes from the United Kingdom. On the decoupage side, she writes about various techniques including craquelure and displays photographs of many of her projects, some of which involve garden-themed items such as watering cans and planters.
http://garden-of-decoupage.blogspot.com/
The blogger shares her projects and information about how she made them. Each one is accompanied by photographs, and many have tips about both creating the items and marketing them.
http://handcreations.blogspot.com/
The manufacturer of Mod Podge hosts this blog, which naturally has a large section dedicated to decoupage. Posts here explain how to go about making magazine collages and how to create designs on glass plates, plaques, and walls.
http://modpodgerocksblog.com/