Concrete Mold Casting Instructions – Original 36″ x 8″ x 2-1/2″ Panel

Here’s the step-by-step guide to making a concrete casting for a raised garden bed using one of our ABS plastic molds.

Casting the Concrete Raised Garden Bed Panels

See the YouTube Video with (even more) detailed instructions and some alternative methods. The 24″ mold produces a concrete casting that weights approximately 33 lbs and the 36″ panel produces one that weights approximately 50 lbs.

Prepare Materials – have your bag of concrete, water, shovel, wheelbarrow, gloves, mask, rubber mallet, small trowel, plastic sheets ready. Level a workbench or similar working surface in a protected warm environment.

Oil the Mold and Pipes – apply an even coat of oil to all inside surfaces of the mold. A small sponge or a clean cloth works well for this. Avoid using excess oil that forms any puddles. While holding the end with the small hole, apply some oil to each pipe.

Insert Pipes – slide the pipes into the holes leaving the pin hole end clear of the mold edge as shown.

Mix Concrete – empty most of the concrete bag into a wheelbarrow or large concrete mixing tray.

Slowly add cold water while blending the contents with a shovel.

I like the mix my concrete so that it still holds some shape in the wheelbarrow instead of so wet that it is fully liquified.

Alternatively, you could mix the concrete in a pail with a blending attachment on a high-torque mixing drill.