One of the most frustrating things about raised bed gardening is that it can often be hard to reach the plants that are growing in the middle of each bed. Luckily, there’s a great solution you can employ if you want to be able to easily access the insides of your raised beds, and it’s called keyhole gardening. There are plenty of benefits that come from keyhole gardening that you definitely don't want to miss out on.

What is a Keyhole Garden?

keyhole garden

A keyhole garden is just like any other raised bed, but it has a unique shape to it that allows the gardener to access any part of it — either from inside the "keyhole" or from around its edges. Most keyholes have circular or horseshoe-like shapes. Most keyhole gardens are also equipped with built-in composting bins, which makes the entire composting process easier on you. As if all that weren't enough, keyhole gardens are also great at retaining moisture. This can be especially beneficial if you live in a hot and dry area, which is why this concept is already so popular in places like Africa, Texas, and Arizona.

Building Your Own Keyhole Garden

keyhole garden in progress

The first thing you’ll need to do when building your own keyhole garden is to come up with a plan for it. Rocks, brick, and wood are all great building materials here. Depending on the size of your area, you'll want to make a garden that's about three feet tall and six feet in diameter.

Using the material of your choice, you’ll want to build up your garden in a circular fashion. When using bricks or rocks, it can be useful to create a foundation as a template and work off of that to get the shape you want. It's best to think of this shape as, well, a keyhole.

If you’re also planning on creating a built-in composting area, you’ll want to take some mesh and use it to make a small circular tube that fits inside the circular center of the keyhole. These tubes are typically about four feet tall and a foot in diameter (assuming you’re making a six-foot-wide keyhole garden).

Filling the Keyhole Garden

Once your keyhole garden is built, you’ll want to fill it. You'll find it helpful to stock up on newspaper, cardboard, and other composting materials before building your garden so that you’ll have more than enough when it comes time to get started. Line the bottom and walls of the garden with those same materials. You can then add layers of additional compostable materials, including little sticks, leaves, and lawn clippings, on top of this bottom layer. Get these layers wet as you apply them, just like you would in a traditional compost bin. The very top of the keyhole should be filled with your favorite blend of potting soil and (you guessed it) compost. Make sure that the soil here slopes downwards from the center of the bed.

You may find that the soil starts dropping as the compostable materials you included inside of the raised bed start to decompose over time. To keep the level where you’d like it, simply add in some more soil.

Filling the Compost Bin

keyhole garden with a full central compost bin

Even though you've already put a significant amount of compostable material into your keyhole garden, you’ll still want to fill up that central compost bin as you go along. Throw food scraps, coffee grounds, lawn clippings, small amounts of paper, and other compostable materials in here. Just make sure that the first layer you put down in ths tube consists primarily of rocks, which will improve the drainage of the bin and allow water to seep back into the soil.

Other Options

When it comes to personalizing your keyhole garden, there are all kinds of configurations you can experiment with to make yours your own. Set up some poles around it and drape a tarp over them to cover the garden, give yourself a longer growing season, and provide the bed with shade during the hottest months. You can also add a roof to your compost bin to help funnel water towards the garden’s soil rather than into the already-moistened compost. Some gardeners even add fencing around the perimeter of their keyholes to prevent deer from making a snack out of their plants. The possibilities are practically endless.

If you aren’t up to designing your own keyhole garden, there are also several on the market that you can purchase to build.

At the end of the day, you'll find it much easier to keep up with your composting and gardening chores with one of these handy raised beds in your yard.