Hebel block planter boxes

Hi All,

I need to make a couple of largish planter boxes to fill/hide a wooden retaining wall along the neighbours fence. I will be planting a couple of bouganvilliers in them and train them along the fence. They can only be about 400mm wide and up to 1200mm long. If you look at the photo, I want to put them behind the water feature wall on top the rock retaining wall to hide the wooden fence/wooden retaining wall.

Would hebel be ok for this or do i need to use something stronger.

Cheers

Michael.

I'd give it a crack. However - I'd pour a small slab to put them on, and pin the joints with stainless or gal screws as dowels and two-part construction resin like Anchor-Fix. Then waterproof the inside with a cheap brushable membrane like Bitcote #3. Don't forget adequate weepholes!

Cheers, Adam.