I get almost 5 pounds of food per square foot from this simple, organic, and sustainable garden
Keyhole Garden in May 2022
My keyhole garden turned three years old a few weeks ago and it continues to amaze.
Aside from a few days halfway through its first year, it’s been in non-stop production the entire time. Baking heat, freezes, pouring rain, wind, it doesn’t matter, nothing stops this thing.
Right now the early spring crops – leaf lettuce, broccoli, carrots, peas, red and brown onions, dill, and parsley – are giving way to early summer crops – tomatoes, bunching onions, summer squash, basil and cilantro. It’s basically a whole food garden packed into one 8 foot circular bed.
If you’re not familiar with the keyhole garden concept, it’s a circular raised bed with a composting bin at the center. A notch, like a keyhole, is cut into the side of the bed to allow access to the compost bin. The bed’s height and shape provide good drainage and easy access from any angle, while the compost bin leaches nutrients back into the bed keeping the plants in it happy and well-fed.
Another advantage of the keyhole garden is one I wasn’t aware of when I first built it. It turns out the compost bin’s activity acts like a little organic radiator keeping the soil surrounding it quite warm even when the weather’s cold and ugly for an extended period.
A peek in the Keyhole Garden Compost Bin
In the late fall the plants’ roots dig into the warm soil and continue producing for a much longer time than would otherwise be possible. In my case, where it freezes overnight often enough but doesn’t snow, I’ve had bell peppers, tomatoes and basil growing alongside broccoli, carrots and onions all winter (I don’t even cover them).
In April of last year I estimated we harvested about 150 pounds of fresh herbs and vegetables a year in the first two years – roughly 1-½ pounds of food per square foot of keyhole garden.
Not too bad.
Later that spring I mastered a few tricks for “pie slice”, “high-low”, and succession planting (more on those later) that allowed the garden to more than triple its output, so we’re getting close to 4-½ pounds of fresh food per square foot. Oh, and all with no additional fertilizer or soil beyond what the compost bin provides.
Now that’s great!
Add in that it helps us reduce our food and green waste to near zero, and my total investment was less than $200, and you’ll understand why I think the keyhole garden is incredible.
If you’re considering your own garden and you want something that’s inexpensive, organic and sustainable, you definitely need to give the keyhole garden a try.