What’s in a Keyhole Raised Bed?

June 20 ,2014 BY Nova Nelson

Great design, plenty of nourishment for your plants and much more.

Design is a big part of my food growing routine. At the start of any project I spend hours observing and designing before I start planting. One garden element I've come to adore is the Keyhole Raised Bed. It displays function beautifully.

Three questions kept cropping up when I first started designing the space for the Think Green Community Garden, a community engagement programme by E&O Berhad; How can I create a productive, space conserving and nourishing raised bed? How could we showcase different ways to compost? And how could we do this by drawing attention to the garden?

Why the Keyhole Garden bed?

I first learnt about the Keyhole Garden bed during a Permaculture workshop I attended but when I saw how communities in Lesotho were using it I thought this would be a lovely way to showcase a way to compost while creating a productive garden bed at Think Green.

Besides its aesthetic appeal, a Keyhole Raised Bed provides many benefits:

1. More space to grow food. The circular design, depth and diameter of the raised bed provides more area and space for plants compared to linear raised beds.

2. Integrated composting. The center basket provides fuel and nourishment to your raised bed. During our collective gardening sessions with children at Think Green, they've learnt how to repurpose garden waste by placing it in the center basket.

3. Adaptable. You can create a Keyhole Garden Bed using a wide range of materials. We've decided to use bricks at Think Green because this food garden is located on a public park that is facing the sea. With strong winds and sometimes heavy rain pelting away we had to make sure it was a sturdy feature. Depending on your site and dimensions, there are many other materials you could consider – rocks, wire mesh and cardboard, galvanised culverts, logs. If you have time, you can build and create your own soil through mulching and layering recycled organic materials (cardboard, mulch) instead of buying soil to fill the Keyhole Garden Bed.

4. Diversity in a small patch. The space and depth you create provide a suitable home for many different plants. If you lack space this one feature can be where you grow most or all your edibles. Giving you an opportunity to mix herbs with vegetables and try out companion planting.

5. Reduces need for watering. Because of the moisture from the the center basket, you will find that you need not water this raised bed as often. Compared to other beds that can dry out.

Some of the considerations before you build one:

1. Sketch before starting anything. Observe, measure up and decide on size and height before bringing in your materials. I've shared the design and dimensions used at the Think Green community food garden below. You can adapt the design to also make it wheel chair accessible or make it shorter or smaller for children.

2. Get help. If you want a high sturdy bed you may need some help from a brick layer. Building this can consume a lot of time and energy. So get some friends and family together to pitch in – throw a collective gardening session.

3. The soil will need topping up from time to time, but with the compost basket in the centre you will have plenty replenishment. You can do this in between harvests or as part of your fertilising regiment.

We've been using the bed at Think Green since July last year and compost at the bottom of the basket is great. The community have grown plenty of local herbs; false daisy, king of bitters (hempedu bumi), Indian Borage (lemuju), Cat's Whiskers (Misai Kucing), Pennywort (Gotu Kola/Pegaga), mint, Thai basil, sweet basil to name a few. We've also had some lady fingers grow really well in the bed. We plan to introduce other vegetables soon.
New to Cultivate Central? Click here to read our manifesto.

If you are thinking about starting your own food garden and need a constant supply of ideas and tips follow us on our facebook page. Thanks for dropping by!

Nova Nelson

Nova Nelson started Cultivate Central in 2013 after transitioning from a career in Corporate Communications, content creation and community engagement. As a Permaculture Designer she believes a city filled with vibrant, ecological and compact urban gardens will create socially and environmentally connected communities. As a mother she is passionate about exploring Permaculture with children and their communities. She serves clients and communities in Malaysia, where she was born and Singapore where she currently resides.

Ready for free resources?

Ideas, tips and other great material to help you create your urban garden - right to your inbox