Concrete garden spheres add curb appeal or enhance your backyard with whimsical hardscaping. Think of them as a modern interpretation of the classic garden gnome!
This post is sponsored by Quikrete
Nestle these spheres between plants or use them to accent porch steps or the patio. No matter where you put them, they’ll make a great conversation piece.
Here’s how to make your own.
- 4 hollow half foam balls
- Hot knife foam cutter
- Planter or container filled with dirt
- Quikrete 5000 Concrete Mix
- Nitrile gloves
- Eye protection
- Mixing container
- Drill with a mixing paddle
- Garden trowel
- 120- or 150-grit sandpaper
Create the Forms
You’ll need two hollow half foam balls for each garden sphere you want to create. I’m making two spheres at a time, so I’ve got four half foam balls.
First, use a hot knife foam cutter to make a 2- or 3-inch-diameter hole in the tops of two half foam balls. (These will serve as the spheres’ tops, in which you’ll pour the concrete — but we’ll get to that later.)
Then, set the other two half foam balls in planters or containers filled with dirt to hold them steady. (These will serve as the spheres’ bottoms.) Stick toothpicks into the rims of each bottom half foam ball and apply caulk all along the rims. The toothpicks keep the top foam ball from shifting, while the caulk creates a seal so no concrete mix seeps out.
Place the other two half foam balls on top of the bottom half balls, ensuring the toothpicks connect the bottom halves with their tops, all the way around. Wait for the caulk to dry. Most silicone caulk takes 24 hours to dry, but some fast-drying caulks only take one to three hours.
Mix the Concrete
When the caulk is dry, you’re ready to mix the concrete. I’m using Quikrete 5000 Concrete Mix because it strengthens quickly.
Tip: When working with cement-based products, always wear a mask, eye protection and nitrile gloves.
Use a drill with a mixing paddle and follow the bag’s instructions for mixing.
Your concrete mix should look like oatmeal — if it doesn’t, slowly add more water to get this consistency.
Fill the Spheres
Once the concrete is thoroughly mixed according to the instructions, scoop it into the forms with a garden trowel until they are full.
Quikrete 5000 Concrete Mix takes about five days to cure in warm weather (70 degrees Fahrenheit or higher) or seven days in colder weather (50-70 degrees Fahrenheit).
Remove the Foam
After the concrete cures, remove the foam balls.
For easier removal, cut long triangles along the balls with the hot knife to help leverage the form off the concrete sphere.
Sand Any Imperfections
Once you remove all the foam, sand the entire sphere with 120- or 150-grit sandpaper for a smooth finish.
Sealing concrete is always a good idea — it will keep the garden spheres from getting moldy, and it will add a slight sheen. Use Quikrete Acrylic Cure and Seal once the concrete has hardened and the surface sheen has disappeared.
Now, all that’s left to do is decide where you want to show them off in your garden!