This turned out to be quite a project, mostly due to the volume of concrete. I was interested in what the concrete would look like if I had to do consecutive pours. My small concrete mixer will only handle about 2 bags of 80lbs concrete at once, so it was an all morning effort. These planters equal about seven consecutive pours (3.5 per planter), with each one taking about 25 minutes to mix. In the end, I think each planter weighed about 300lb pounds. That means I couldn’t really move them by myself, which I don’t like, so in the future I’ll make sure projects like this are more manageable.
What I’d do differently next time:
• make the walls thinner, to use less concrete and make the whole thing lighter
• the foam knockouts were a pain to remove. In spots concrete seeping in between the foam knockout layers made removing the knockout even harder than it already was. Not sure how to improve this except maybe use alternate material.
This was an adaptation on a design from Cheng Concrete.