Food Forest: Site Preparation

Wetlands Passage under concrete

When I initially into Orange Grove, I knew that I wanted to slow and sink water in a narrow passage that I saw as an urban food forest. My primary concern was with harvesting water and I had two possible sources: rain harvesting from the roof into containers or tanks and harvesting from rising water which collects in a French drain in my basement.

My first step in creating an urban food forest required removing the concrete in the passage/servitude.

This area is a semi-shaded one. It is also part of the Paterson Park Wetland. During the rainy season water gushes down – from drainpipes, not just from heavy rains in summer. With the increased volume of water, the water table rises and sometimes my basement gets flooded. To alleviate this, two actions were needed. One was to direct the water away from the foundations of the house and from the basement. The other was to replace the pipe leading from the French drain onto the street. It also required removing the concrete that currently blocks the outflow.

Fortunately for me the house was well built – the only real risk that I see is caused by the blockage mentioned above, and by ‘flash floods’ when downpours turn the passage into a ‘stream’ sometimes allowing water to penetrate into the basement. I have more serious damp problems in a cottage built more recently, but that is another story…

French drain in basement

French drain in basement

In my original design I imagined water flowing in a straight channel down the centre of the passage and ending in a wetland pond at the end of the garden. I imagined I could slow and sink water by using terracotta pots in makeshift semi-circular swales. What I had in mind I think came from childhood memories of channels with water that could be slowed or redirected. I envisaged pots with water-loving plants placed in these channels, obviating the need for watering. (I am fond of solutions that diminish the need for labour.)

I had an additional desire; I wanted to filter water in this area. My thinking was that if it feeds the water table then it should be as clean as possible. Secondly, since the excess water runs into the storm water system which in turn flows into Paterson Park Spruit, it should be as pure as I could make it; I wanted to do my bit to alleviate the challenges that the wetland faces.

Initially I wanted to add biochar for a really clean effect as I envisioned a wetland/water garden at the end of the property. I spent months trying to see how I could do it, for biochar needs to be replaced at regular intervals. The horticulturalist I consulted saw it somewhat differently. There is no real need for biochar; the passage itself could be the water garden using bioremediation wetland plants. With her design I can still sink unglazed terracotta pots filled with herbs or vegetables or vines in the water garden. (Unglazed terracotta allows for water to permeate into the pots, removing the need to water the plants.)

Unglazed terracotta pots used as a swale

Unglazed terracotta pots used as a swale

I also wasn’t sure that I would be able to plant trees directly into the ground for fear that the tree roots might damage the foundations of the house and/or the boundary wall I share with a neighbour. I therefore intended to have these in pots as well.

However, after the consultation, I have decided to plant some trees directly into the ground. (It was suggested that a 15-20cm apron of concrete be left around the foundations of the house. This has been done. The wall will be sealed using Coprox, and the base, where the house and concrete meet, will have a curved edge directing water away from the foundations and into the water-garden.)

This comes at the end of an eighteen-month period during which I have observed the elements as they interact in different parts of my property. I have also made an effort to understand how the water from my site impacts on neighbouring properties as well as on the water cycle. While I retain concerns about possible contaminates penetrating into the water table and thus the water in my basement, I am happy that the systems I am putting in place align with some of the principles of permaculture.

To resolve larger challenges, I will continue to work with my community, for sustainability at every level, not just the individual one, is an ongoing process rather than an event.

Indigenous trees and plants for micro-climates

When searching for information on indigenous trees, I tend to favour Plantzfrica (http://pza.sanbi.org/). It is particularly useful when I know the names of the trees I am researching.

Plants in different types of pots

Plants in different types of pots

However, when I want a quick list of indigenous trees, or other plants suited to particular climates or micro-climates, I prefer to use Grow Wild’s website (http://growwild.co.za/). It has a number of filters that I find useful. From this I can verify my list against theirs and if I want more specific information, I then use the SANBI site.

Containers for plants

From Margaret Roberts Herbal Centre I purchased a number of herbs. Some of these I repotted in unglazed and glazed terracotta pots, tin cans, dried gourds and plastic. Sadly, some plants are like children who like what the parent knows is not good for them – too many of my plants thrive in plastic! This is especially true in winter. Cans, I have found, are the least popular with the green family, so I will curtail their use.

Nonetheless, by moving my potted plants around I have learnt where the various plants might thrive. As soon as the infrastructure for the water garden is in place the pennywort and the houtinia will find a home, as ground covers. I like the integrated plan.