How to build a Keyhole Garden

First made popular in Africa, keyhole gardens are catching on in Texas and other hot, dry places. Keyhole gardens hold 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.

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. They use kitchen and garden waste and gray water (or wash water) as food for your garden.

Materials
Large stones,bricks or logs
Straw or dry sticks
Garden twine
Several 5ft garden canes or similar
Broken plant pots or tin cans
A length of wire
Mixture of well-draining topsoil and compost plus some well-rotted animal manure

Instructions

1. Dig over a space of 3 square metres. Tie a stick to each end of 1.2 metres of garden twine. Place one end in the centre of your space and use the other to mark a circle in the ground. Then draw out of an entrance triangle, from the circle to the centre starting at a width of 60cm.

2. Lay down the canes 5-10cm apart. Wrap wire around each one, attaching it to the next untill they are all in a line, do this at the top and the bottom of the canes. The total length should be about 130cm. Now make this into a cylinder and push into the ground at the centre of your space. Half-fill this ‘compost basket’ with top-soil to make a mound and line the inside of it with straw.

3. Lay your stones,bricks or logs around the perimeter of your garden – this could be a single layer or more, but enough to keep the soil in. Build the stones higher at the entrance triangle. Make the first layer of the garden from broken plant pots or cans to improve drainage.

4. Now start filling the garden with the soil and compost. Make sure that the best soil goes on the top. Keep piling up the soil until you have a mound which slopes away from the basket.

5. Let the garden settle a week before planting your seeds and seedlings. To start with, water the soil surface until the roots grow, then water the basket with waste or rainwater, using the entrance. Add already composted material to the basket and continue to add compostable food-waste. A circle of carpet over the top of the basket will help speed up the composting process. The compost will permeate the garden and give your crops lots of nutrients.