Modern DIY Concrete Planter

This is my first attempt at making something with concrete. There are many different types of concrete, in terms of shades of greys, smoothness, and time to cure. I wanted these planters to be as white as possible so I bought a special type of concrete that is very white and smooth.

It’s expensive in comparison to something like Quikrete that you can pick up at a big box store, but the results are worth it as its properties lend itself to a great modern look.

To learn more about the differences between different types of concrete and cement craft mixes, download my  Free Pocket Guide To Cement and Concrete Crafting Mixes.

Choose your mold materials. Keep in mind that every line and indent will transfer to your planter, so the smoother, the better, so make sure whatever you choose is pliable. In other words, if you can bend it now, you should be able to remove it without much effort from the concrete when finished.

Also be sure that when you put your inner mold into the outer one, that it gives your planter walls that are at least ¼” thick because it will help avoid cracking.

To make mixing the concrete easier, tape two paint sticks together. Just wrap the tape around each end.

Pour cement into the bucket. I used a ratio of about 3 ½” cups of concrete to 1 cup of water.

Now add the water and mix it in, if you need to add more, do it slowly. It should be the consistency of peanut butter.

Pour the concrete into your mold. Shake and tap to get the concrete to settle. If you want to eliminate air bubbles, use an orbital sander- without the sandpaper to vibrate from the sides which will release the bubbles.

To help lubricate, rub the cooking oil around your plastic for your inner mold and then insert it into the outer mold.Note: The concrete may bevel upward when you insert your inner mold, so keep tapping the bottom of the mold on your work surface until it flattens out again.

Clean up your edges with a sponge so you will have less sanding to do after it cures. Also, be sure that everything is level.The concrete will likely resist the inner mold piece and push it up.

You will need to add something on top that has some weight to it to avoid this. In the photo, I used a glass vase with a small black vase that was pretty heavy and fit inside.

To get tips and details on concrete mixes, sheens, sealers and more, check out the  cement tests post I did!

Let the concrete cure for 24-48 hours, keeping the weight on top. If you can wait 48 hours it will be safer and help avoid cracking.

After curing and you have removed the weight, this is what it will look like.

When cured, very gently pull out your inner piece.