Experts and BHG readers answer.
Rocks, rocks and more rocks
We have a story on this topic right now in the Spring 2010 issue of Deck, Patio & Pool. Basically, you have to dig into the slope, create an even, compact base of gravel, then stack the rocks carefully. The slope of the wall needs to taper back, and rocks should fit snugly. Using mortar will strengthen the wall. Also, it is best to install a drainage system (gravel and perforated plastic drainpipe) behind the wall to keep the weight of water from destroying your retaining wall.
For more specific information and step-by-step illustrations, consult the Ortho Start-to-Finish Landscape Construction book (2004, Meredith Corp.).
Luke Miller, editor
Garden Ideas & Outdoor Living magazine