First made popular in Africa, the keyhole garden is catching on in Texas and other hot, dry places. A keyhole garden holds moisture and nutrients due to an active compost pile placed in the center of a round bed. Although most helpful in hot and dry locations, a keyhole garden will improve growing conditions in just about any climate.
How a Keyhole Garden Works
From a bird’s eye view the garden is shaped as a keyhole. A notch is cut into a round garden bed. The notch makes for easy access to the center compost well.
This sustainable gardening method uses kitchen and garden waste and gray water (or wash water) as food for your garden.
Layering is proven to enhance soil health. Layering suggestions from Texas Co-Op Power: Wood on very bottom, next cardboard, next a bit of compost, next petroleum-free newspaper, manure, worms, wood ash, straw, topsoil. Repeat, compost, straw, topsoil or some such combination until you reach desired height.
When it rains or when you water your compost, the nutrients will seep into the surrounding bed. During rainy spells you might wish to cover the compost so the nutrients in the compost do not leach out too rapidly.
Felco F-2 Hand Pruners
Whether your garden is round, square, or keyhole, these pruners will become one of your favorite tools. The handles are forged aluminum, the blade is hardened steel. The handle even includes small shock absorbers to protect your hands and wrist. Simply the best on the market—and it comes with a lifetime guarantee.
Keyhole gardens have been made popular by Send a Cow, a humanitarian aid organization which builds keyhole gardens for families throughout Subsaharan Africa. Three keyhole gardens can supply a large family with all their vegetables for a year.
Keyhole Gardens Around the World
At Keyhole Garden in Central Texas, Deb Tolman uses keyhole gardens as the main source of her own food supply, and is working on ways to keep them producing throughout multiple seasons and conditions. Dr. Tolman incorporates a frame into most of her designs to support a shade cloth during the hottest months. The frame might also be covered in early spring with plastic sheeting to create a greenhouse. Dr. Tolman is available for workshops, consultation, and seminars. Photo by Dr. Deb Tolman.
Keyhole garden in Lesotho by Send a Cow, which first popularized keyhole gardens in Africa. Send a Cow has helped countless families and schools build keyhole gardens.
This keyhole garden by Send a Cow looks easy enough to set up, but the bricks do not look like they will take another level if you want to make it bigger someday. The compost adds more and more soil year after year.
In this keyhole garden by Send a Cow, the builders have lined the center well with sticks, or with chicken wire lined with straw, to separate the two areas. The center well is used to irrigate the whole garden, bringing nutrients from the compost into the surrounding soil. www.sendacow.org.uk
A keyhole garden in Ethiopia. Keeping a lid on the center well will retain heat and reduce evaporation. Photo via dsnyderphotography.com
Keyhole garden in Rwanda by Send a Cow.
Keyhole garden in Uganda by Send a Cow.
Keyhole garden with a surround of sticks in Uganda by Send a Cow.
Keyhole garden by Send a Cow.
Keyhole gardens wrapped in wood, by Deb Tolman of Texas. In the winter the compost in the center of the keyhole garden generates heat and holds moisture. See the Keyhole Gardens Facebook page.
Keyhole Vegetable Garden by Anne Hars, lined with straw wattle.
Keyhole garden by sixth grade students in the UK, who had been learning about sustainability and the soil conditions in Africa. The children used a combination of bricks and stones to create the garden. They surrounded the center compost with a piece of willow fencing. A garden sieve was then placed on top of the compost area to allow the rain water to seep through the compost and into the garden to help enrich the soil. Each day children throughout the school place their fruit scraps and more into the compost. The children used the proceeds from selling their produce to help buy a goat for a third world country through OXFAM.
Keyhole garden in Florida by Melissa Contreras. This garden can grow in height, as the compost adds volume, more bricks can be stacked as in the image below.
Keyhole garden by Freddy Hill of Oklahoma.
Keyhole garden in Texas by Deb Tolman. Says Deb: “If all the layering guidelines have been followed, watering is at a minimum, evaporation is at a minimum, all plants look nutrient-fed, and productivity is high.”
Keyhole garden in Texas. “Layered in the bed are bones of two cows, ash from one brush pile, aged dried poop from a dozen cows, five bags of clover, a pile of forest floor mulch, cardboard, rusty items, and 15 buckets of two year old compost.”
The reuse ideas are endless—cans, metal, old row boats…earthbags…logs. This is a wine bottle keyhole garden by Mary Martine of Phoenix. “800 wine bottles, one year from conception to completion, and a lot of faith that this crazy idea would work. The diameter of the circle is approximately 7 feet.”
Beer bottles in cement. No keyhole. Love the bottle reuse, looks sturdy. Frame is for a shade cloth. Via www.facebook.com/keyholegardens
Keyhole garden by Jim. Via www.organicgreendoctor.com
A keyhole garden built by students in the UK. Flowers surround the vegetables. Via
How to Build a Keyhole Garden
Step by step video of a keyhole garden build from Liberty Garden.
Sloping the soil away from the center well allows better transfer of water and nutrients and adds to surface area. www.sendacow.org.uk
A two-page, printable, very visual, keyhole garden building guide from Send a Cow. Bright, colorful, good for kids.
A visual but slightly more dry two-page printable keyhole garden building guide from the Baker Institute.
Photos and a 10-step keyhole garden building guide from Texas Co-Op Power.
Written instructions on how to build a keyhole garden from TECA, a program of the Food and Agriculture Organization of the United Nations.
KeyholeFarm.com sells a keyhole garden kit, starting at $289.
The Best Keyhole Garden And Small Garden Books
Plant Your Garden In A Keyhole by W. Leon Smith
Soiled Rotten: Keyhole Gardens All Year Round by Deb Tolman, Ph.D.
Gaia’s Garden: A Guide to Home-Scale Permaculture by Toby Hemenway