As some additional pre-garden work, we built a low retaining wall around the lower part of our garden!
The border of our existing garden was laid out with stones, but because of the slope of the hill that is the whole yard the border had eroded on the eastern edge and wasn’t in amazing shape. We wanted to touch things up a bit before planting, and thought a low retaining wall would be pretty snazzy and not too difficult.
Well, it wasn’t extremely difficult, but like any home project it took much longer to complete and was a bit more frustrating than we thought. Overall, it was a manageable project for retaining-wall beginners such as ourselves.
First thing’s first, we dug out most of the stones that bordered the garden. Ultimately, we only built a new wall on the lower edge of the garden, but the border needed redoing anyway as it was a bit overgrown and eroded in other places.
Then, we dug out part of the garden to re-define the border. When building up a retaining wall, you need to dig a trench several inches down and several inches deep, to fit the stone plus a base material – crushed stone or paver base, which we used. In retrospect, it wasn’t the best quality paver base, but hopefully it will be good enough to hold up our wall. The amount of paver base needed depends on the height of the wall you intend to build – we only built a wall about a foot or so tall, so only needed a few inches of paver base beneath the stones.
We measured out where we wanted the wall to sit, and placed a reference line. We intended the line to mark the height the stones would come to so we knew how deep to dig the trench, but ultimately it only served as a guide for the wall edge, as our height measurements were off. As a result of the line being off measure, we laid more paver base in a few places than was needed.
Once the trench was dug, we tamped down the dirt so it was packed well, then poured paver base over that and packed it down to level and was at appropriate thickness.
Then, we started laying stones. It was very fiddly work getting each stone placed, leveled front to back and side to side and with respect to the adjacent stone.
John thought to lay a test stack of stones for one corner, to work out the turn before starting for reals. We wanted to start in one corner, work across the front, and work the second corner (dig out more garden/trench if needed) to get the fit about right.
The base layer of paver stones was the hardest part; after that we were able to stack stones on top fairly quickly. The 12x4x7 pavestone blocks we got from Home Depot have a locking flange on the back, which interlocks with the stone beneath it when stacked. We stacked the stones 3 high. Before the next layer of stones, we filled in behind the previous layer with dirt.
We worked on the edges after finishing the front and corners. We didn’t need the lowest level of stones to run the full length on the left side, as the ground level on the outside of the wall was higher, and the stones would be fully buried under several inches of soil. On the right side, the lowest level of stones runs the full length.
The project took about a week and a half to complete, from moving the original stones and digging out the garden to completing the wall.
Also, and this was only useful at the very end of the project, we got a free wheelbarrow from the previous owner of the house. The tubeless tire was flat, but John was able to re-seat the tire onto the rim and inflate it. Yay free wheelbarrow!