If you live in an area that is very dry or where you have a very limited water supply you may want to consider doing an eco-circle. So what is an eco-circle? It is simply a circular shaped garden bed that is located in a sunny spot, as close as possible to a reliable water source and where you are able to protect it from animals such as chickens and goats.
The soil preparation is similar to the method described in the door/square veggie garden in that you want to mark out your circle (any size would do but in my experience a 2m diameter is the largest you should go) and then dig out the soil to a depth of a least 50cm.
Once you have your hole dug the next step is to place a container in the centre of this hole. The container must be proportional in size to the circle and so for a big circle of 2m diameter I would use a container the size of a conventional black rubber rubbish bin and for a smaller circle of say a metre, a 25litre paint tin would do. Obviously the container needs to be clean and free of toxic materials that may have been stored in it. This container needs to have some holes drilled in the side towards the lower third of the container and evenly spaced around it. The holes must not be large as the idea is for the water to be able to seep out into the soil once you have filled up the hole. I also try and cover this hole with a piece of shade cloth on the outside of the container simply to stop the soil from entering the container. In a rubber rubbish pin I would simple staple the shade cloth to the bin or simply pile the soil up against it to hold it in place. It is also important that the top of the container lies below the level of the PERIMETER of the circle. The whole idea is to gently slope the soil from the perimeter of the hole to the edge of the container so that any excess run off water runs into the container and then seeps into the bottom layer of your soil mix and therefore uses every bit of available water.
If you want to plant immediately then replace the top soil into the hole and fill it up with the best compost and top soil mix that you can afford. I would also add in bone meal (roughly a big double handful for every wheel barrow of soil mix) and some organic vegetable fertiliser at the recommended rate on the package. However if you have the time then you can use this empty circular hole as your compost pit and toss in all your decomposable kitchen waste, garden refuse and lawn clippings. Like the door/square bed you will need to add soil every time you put a layer of compostable down and keep the whole heap warm and damp.
Once the hole is full then ensure that there is a slope towards the container edge and a good idea is to line the edge of the container with some small rocks which will prevent the soil from running into the container but that will allow the water to run into it. So this container is a slow leak reservoir that stores water. So it really is vital not to make the leak holes too big as you do not want it to empty too quickly. It is also a good idea to knock up a simple frame with shade cloth stretched over it and cover the top of the container. This simply cuts back on evaporation, prevents small creatures from falling into it and drowning and mosquitoes laying their eggs in it.
You can now plant up the circle with your favourite herbs and vegetables. I normally plant a perimeter ‘hedge’ of wild garlic. These tough plants will keep the perimeter stable, define the circle and the pungent odour from the leaves will help chase away nunu’s. Your lines should then run in circles or you could simply randomly plant in a more naturalistic way. I once planted some comfrey around the container edge (on big circles only as the plants get big) and would regularly prune the leaves off and place them in the water to ferment and then used the water a liquid tea.
A wonderful contact organization is www.soilforlife.co.za Please have a look at their site and if ever you are in Cape Town I would recommend that you pay them a visit.
