Kevin and Faye built a garden bed using concrete blocks and a MITREPLAN. They
chose blocks because they match the existing garden wall, but they’re also a
fast way to build, and accessories like capping and pre-formed corners make the
Step 1: Set up the work area with all your materials and equipment close at
hand. Keep your mortar or cement dry. Clear away any debris, plants and turf in
the area where the blocks will be laid.
Step 2: Dig a shallow trench for the mortar bed. There’s no need for concrete
footings when the wall is only a couple of courses high. Then sit the blocks in
place to check where the cuts will be. Use the 3:4:5 triangle method to make
sure your setout lines are square. Mix your mortar in a barrow or on a board,
adding a little water at a time until it’s wet enough to easily make a furrow
with a trowel, but not so sloppy that the furrow collapses.
Step 3: Place stringlines to give you a level and straight line for the outside
edge of your blocks, then set the first corner block in place. Tap it into place
so that it aligns with your string, then “butter” one end of the next block and
tap it into place, cleaning off excess mortar as you go with your trowel.
Concrete blocks have an open and closed side – the open (holes) side goes down,
so it beds-in better, and the closed side goes up so the next bed of mortar
won’t fall down the holes.
Step 4: Cut blocks with a wet saw or angle grinder fitted with a diamond blade.
Step 5: Lay the next course by spreading a “sausage” of mortar on the previous
course, making a furrow with your trowel and setting the next block straight,
level and plumb. Offset each block by half to get a normal brick pattern (called
Step 6: Cap your garden wall with treated pine if you want a seat, or simply
glue down the precast concrete caps with Selleys Liquid Nails Landscape. Use
plenty of glue, and wiggle the capping to bed it down.
Step 7: Fill up your new garden with plants! The mortar will dry and set over
the next few weeks, so you’ll have to wait if you want to paint it.
Faye and Kev's Tips:
Wet the blocks
before laying to prevent them from sucking water from the mortar mix.
Get a hand if possible; it’s much quicker and easier if one person mixes
“mud” while the other lays the bricks or blocks.