Practical permaculture techniques (Oct. meeting recap)

These are the notes from my presentation on permaculture. Download the accompanying handout here (PDF, 736kb). Be sure to register for an account at this website if you'd like to leave a comment!

Permaculture: Intro

Permaculture was started by Australians Bill Mollison and David Holmgren as a response to the oil shocks of the early 70's. They realized that our reliance on fossil fuels, particularly in agriculture, was unsustainable and that it was necessary to create a parallel system that wasn't so dependent on outside, finite energy inputs.

Permaculture is a combination of the words "permanent" and "agriculture" or "culture" - Mollison and Holmgren originally began by studying and mimicking patterns and processes found in nature to create an agricultural system that did not deplete the Earth's resources. They extrapolated that to develop a philosophy and a sustainable system for all aspects of human activity – small balcony gardens, back yards, whole properties, even city design. The principles of permaculture can be applied to our garden or to pretty much any other aspect of our lives.

I covered the 3 ethics of permaculture in the September newsletter, there will be an article in the November 2007 newsletter about the 12 main principles of permaculture. Dean and I have started a community group called SustainaBundy, with the goal of using some of the 12 principles of permaculture to make a sustainable Bundaberg – if you want more information about that, come talk to us or visit sustainabundy.org

Today I want to talk about some of the practical permaculture techniques that can be put into place in our own back yards. When you read the permaculture article in the newsletter, think about how the 12 principles apply to these techniques.

Plant Guilds

Guilds are associations of mutually beneficial plants, which in some cases use the idea of companion planting.

For example: if you plant chili and some beans in the same hole as a banana sucker, the beans fix nitrogen in the soil, the banana provides support for the beans and the chili prevents beetles from attacking the banana. This is one example of a plant guild.

Another is the traditional Native American "Three Sisters" garden: corn, squash and beans. The big squash leaves shades the soil, which helps retain moisture and prevents weeds and the prickly leaves help deter pests. Beans fix nitrogen, which the corn needs, and beans use the corn as support as they grow.

Guilds can also take into account best use of space, these work well if you don't have acres to work with. For example, the Seven Layer Food Forest.

The seven layers consist of:
overstory trees (large fruit/nut)
understory trees (dwarf fruit, shorter trees)
shrubs (currants/berries, nurse plants - nitrogen fixers, shelter/shade for young trees, etc)
herbaceous (herbs, comfrey)
ground cover (strawberry, legumes)
roots (tubers)
vines/climbers
(potential 8th layer – fungi)

Example:
Over: ice cream bean
Under: plum
Shrub: pomegranate
Herb: sage and woody herbs
Ground cover: sweet potato
Vines: passionfruit, kiwi fruit, choko
Root/Tuber: onions, taro

The Banana Circle: a guild that uses permaculture principles and the layered food forest concepts

How to:

1. Dig a hole, 2m wide and 80cm deep
2. Pile the soil into a bund around the perimeter of the hole (if you're on a slope, build a crescent instead of a bund)
3. Create a way to route greywater into the hole via a pipe or swale – but make sure to use only use biodegradable/natual soaps, cleaners, shampoos, etc (bicarb works great for all the above)
4. Add cardboard/newspaper in the hole
5. Plant your banana suckers (5 or 7) on, in or outside of the bund depending on your soil (ie for fast draining soil that doesn't hold water, just inside the bund will work better
6. Put all your compostables in hole, include banana leaves, spent banana stems
7. Plant your guild/forest plants based on need (sweet potato on the bund, watercress in the centre where it's wet, etc)

Keep the banana trees tidy, remove broken leaves and mulch them in the centre immediately to avoid rot and snakes.

When your banana fruits, remove the fruit, cut the original stem, chop it up and add it to the centre compost pile. Leave one sucker per plant to continue the circle and remove other suckers - use them to create additional banana circles if your greywater production is high. Create a second pipe or swale in your original circle to route extra greywater to the new circle. Banana circles can be chained like this indefinitely if you have enough water to warrant it.

Benefits of a Banana Circle:

-Centre compost pit produces a good amount of healthy topsoil
-Treats greywater before it goes to the water table by using up the nutrients
-Adds extra edge for growing space and variety, retains moisture
-Creates a series of micro-climates for different plants' needs (dry, full sun on the outer sunward side of the bund, moist, cool and shady inside, dry and partial sun on the other side.) It can even create rain within the circle!
-Can take a lot of abuse - some places put a grid in the pit and use the circle for outdoor shower or toilet (this is dependent on the laws in your area!!)

Example banana circle guild/food forest:
Overstory: banana
Understory: paw paw
Shrub/herb: lomandra, comfrey, lemon grass, citronella grass, watercress (can go in centre wet area), poppies
Root: cassava, arrowroot, beetroot, sweet potato (root/ground cover)
Ground cover: nasturtium
Vine: Bean, choko

Have a look at the handouts (PDF, 736kb) for illustrations and more info!