6. Keyhole garden and Mandala garden

Keyhole gardens are generally raised beds and are rarely, if ever, dug up. Continually “feed” your garden by top-dressing it with compost and mulch (to retain moisture). Permaculture encourages the creation of healthy soils wherein worms and micro-organisms do the hard work for you.

A raised Permaculture key hole circular garden bed with bamboo sidings (see graphic) includes a variety of plant species. Permaculture is a no-dig system and by utilizing the keyhole shape, the soil in this raised garden bed need never be disturbed. This allows the micro-fauna to multiply and go about their work of building healthy soil, whilst the Permaculture gardener is allowed easy access for planting and maintenance.

Using a creative pattern in the garden will create more edges and often can increase diversity and productivity. The technique called “Keyhole Garden” is beautiful, simple and productive. It can be adapted to the specific needs of the gardener. One of the basic ideas is that it provides easy access with minimum path-to-bed ratio – a “least path” design. The horseshoe-shaped beds are sized so you can easily reach the entire area standing in the keyhole. The beds can be situated near the house for quick access, or along your main pathway.

The beds can be constructed in many ways. For perennials, the raised-bed method works well. For annuals, the sheet mulch method is a great alternative. Instead of tilling or double-digging to prepare the growing space, start with a weed barrier of wet newspaper (black ink only) or cardboard, layered over the entire area. On top of this, use sawdust or straw to define your keyhole pathway. Then around it, put a good layer of compost for your annuals. You can add a bit of soil or sand to hold your seeds. Cover it with straw or old hay to keep it moist. Now you can plant your seeds or transplant your seedlings and your garden bed is done.


One example is the “tomato-polyculture keyhole”. The bed can be around six feet across and three rows deep, with basil/chives in the first row; then a row of tomatoes interplanted with marigold (tagetes) which reduce nematodes; followed by an outside planting of Jerusalem artichokes or sunflowers to act as a wind-shelter and reflect the sun, creating a good micro-climate for tomatoes.

The keyholes can be used along a pathway or they can be combined around a circle to create a beautiful mandala or circle garden. The center circle can be planted with herbs, flowers, a small tree or a shrub. The center is also a good place to have a small pond in the garden. It would be a great place to sit and enjoy a meal, surrounded by flowers and an abundance of food. And if you need a little more salad you can reach out and pick a few leaves. Enjoy!

This Mandala garden is  based on the keyhole garden. It uses the combination of horseshoe shape to create a mandala like final shape.

Why Mandala Shape?

Besides its aesthetic appeal, non-linear gardens have greater productivity due to the fact that there is simply more gardening space when using non-linear geometry. Linear gardens have their origin in division and ownership of land (easier to mark and measure), and in use of mechanical soil cultivation (easier to drive a horse or a tractor down a straight row). Since neither one of these elements applies to our ecological garden, there is absolutely no need to make them straight! Any shape that respects the landform, works with the flow of water and with the way humans move make more sense.

Mandala Garden as a permaculture design approach is overused, just as is the Herb Spiral. The reason for this statement? Permaculture is not about cookie-cutter solutions that fit all conditions. If you are gardening on a gentle slope, your mandala will not look like mandala anymore (if you are paying attention to the flow of water, and your orientation towards sun) – the shape of the beds will follow the contours, resulting in a geometry both more beautiful and functional. Mandala Shape though is very beautiful.

The primary reason to build a Mandala garden is because it is a time saving as well as resource saving design for a vegetable plot. By having the bulk of your vegetable beds in one large circle, come summer, you only need to put a sprinkler in the centre of the circle and turn on the tap … Bingo, your vegetables are watered with no wastage around the edges and it has only taken one minute of your time.

A mandala garden incorporates several Permaculture practices:

  • keyholes for easy access to plants
  • “no dig” principal to prevent disruption to soil ecology
  • mulching for moisture retention and soil conditioning (it becomes one big worm farm!)
  • planting in different patterns rather than the conventional rows.

Rotation cropping, to prevent excessive build up of certain pests in the soil (e.g. nematodes, phytophthora etc.) is made so much easier to plan and put into practice – you only need to rotate your planting regime by one segment each season.

WHERE should you build your mandala garden?

  • in a sunny spot not over-shadowed by trees or walls
  • on a flattish piece of ground rather than on a steep slope
  • preferably slap-bang in the middle of a wasteful piece of resource-draining lawn
  • if you are adventurous, make your mandala vegetables garden the feature of your front yard, with companion plants like nasturtiums, marigolds and calendula to brighten it up.

How do you build a mandala garden?

1. Choose your site and decide on the diameter of your mandala (six to eight segments is convenient and the diameter of the circle made by your sprinkler on full pressure). Mark it out from the centre point – you can use tent pegs and some string lines for this.

2. Before setting out your segments with bricks/rocks/sleepers etc., sheet mulch the circle after throwing down weed seedy hay, kitchen scraps, lime (if required) and manure, using thick wads of overlapping wet newspaper or old organic  carpet. Water it well. (See Sheet Mulch).

3. Use the bricks/rocks/sleepers to form the segments, leaving enough space between the segments for a narrow walking/picking path.

4. From the centre of the mandala, form a keyhole radiating into the middle of each segment (or form a keyhole from the centre of the outer curved edge of each segment towards the centre of the mandala itself). These keyholes are invaluable for allowing easy picking of your vegetables as every part of the mandala should be at arm’s length.

5. With most of the hard work completed, all there is left to do now is to barrow in top soil (if you have it), some well rotted manure and compost and top with the mulch of your choice – weed-free hay, lucerne hay, rice husks, straw or a sawdust/manure mix.

The paths and keyholes only need a layer of straw over the base sheet mulching, which can be topped up occasionally.

6. Sit back and wait till Spring before planting, to allow the worms to do their work, or even better, plant a green manure crop such as lupins or tick beans (nitrogen fixers) which will later be slashed and left to rot down before your Spring planting.

Handy Hints

1. If you wish you can mark out your mandala circle (taking care to leave your centre marker in place) and plant a crop of potatoes in mulch using the no-dig method. After harvesting the potatoes you will find the soil softened and enriched and worm-infested.

2. After each cropping season feed the mandala with manure/compost, lime, blood and bone, etc., to keep the worms happy and replace lost nutrients.

3. Make the centre of your mandala a useful feature in some way. Alternatively, drag up a chair and an umbrella and sit and enjoy the fruits of your labour and pray for a surplus!

Although the mandala garden will supply you with space for a wide variety of vegetables and fruits, you will probably still need extra beds for mass plantings of vegetables such as potatoes, onions, pumpkins, etc.



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