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Re: Just a few holes in the Permaculture suit?




Hi Ian, Neil and other participants...
Can I add a comment or two in your discussion below....

> From: Ian Lillington <ianl@internode.on.net>
> Reply-To: "permaculture" <permaculture@franklin.oit.unc.edu>
> Date: Sun, 22 Jul 2001 22:34:09 +0930
> To: "permaculture" <permaculture@franklin.oit.unc.edu>
> Subject: Re: Just a few holes in the Permaculture suit?
> 
> I liked Neil's point:
>> Could someone tell me to what extent has the use of Mandala Gardens, Keyhole
> Gardens and Herb Spirals contributed to the home gardeners food production in
> Australia?

It's good to know that you're not alone. For some years I have asked myself
and others around me about the productivity of mandala gardens, keyhole beds
and herb spirals.

To my knowledge, there have been no experiments comparing any of these
things to a conventional, shall we say - rectangular - garden for growing
vegetables or herbs. Unfortunately, I do not have the space to do the
experiments. The assertion that these devices are more effective in
producing food appears to have been taken at face value. Would be good to
see figures from a properly conducted experiment.

The assertion is that a spiral shape offers a greater growing (surface) area
than a flat garden of the same base dimensions.

To test this, what could be needed could be to:

- construct a rectangular garden of the same footprint as a herb spiral
adjacent to it (so both gardens occupy the same microclimate conditions)

- calculate the surface areas of both gardens

- plant both gardens with the same herbs at the same spacing

- provide the same management through the growing season

- calculate the productivity at the end of the growing season by weighing
biomass, assessing the foliage coverage/ exposed soil ratio for each garden
and by calculating the productivity per surface area.

Assessment of a mandala garden could follow an analogous methodology.


MANDALA GARDENS
I understand the notion that mandala gardens are appropriate designs for
intensive vegetable production on flat land and I am aware of the innovative
work of Linda Woodrow (see "The Permaculture Home Garden") in developing the
concept into an intensive food production system including fruit and chooks.

What I have seen with Linda'a design is that (a) you need a large amount of
space  - often unavailable in city gardens and (b) the system is a little
too complex for beginner gardeners; I saw a community garden that wanted to
adopt Linda's design but found it too hard for people with no previous
gardening experience; this does not detract from the validity of Linda's
ideas, of course.

My observations of mandala gardens indicates to me that the critical factor
in productivity (how much food is produced) is closeness of planting, soil
fertility management and adequate irrigation (irrigation is an important
point in Sydney and places north during the hot summer period around
January/ February). Such an intensive mandala garden design was described in
the book "Mandala Gardens" by Robyn Francis.

I have seen a number of scraggly, apparently low productivity mandalas with
lots of empty space that could have supported more plants. The planting
patterns of John Jeavons, described in his book on the biointensive method,
may provide knowledge for gardeners to intensify their soil fertility
through the addition of compost and to close plant.


KEYHOLE BEDS
Many keyhole beds I have seen have the keyhole path too wide...  they have
devoted so much space to the keyhole that they have reduced significantly
the growing area. 

In our organic gardening course in Sydney we tell participants that the
access path into the garden (whether keyhole, soil/ paved path or stepping
stones) need only  be narrow  - wide enough to move into the garden, crouch
down and  harvest vegetables. In our own small home garden we have no
keyhole beds (or mandala gardens - too little space - or herb spirals)...
our access paths are only the width of one and a half house bricks.

HERB SPIRALS
We used to teach construction of herb spirals for two reasons:

- to provide vertical relief in flat gardens - that's more a landscaping
rather than a horticultural reason

- to generate enthusiasm in their construction by students... students
sometimes approached the building of a herb spiral as a sculpture.

We also explained that we did not know whether the spirals produced a
greater quantity of herbs than any other type of herb garden. We show an
example but do not teach herb spiral construction in our organic gardening
courses.

NEIL's QUESTION
Neil asks: "what extent has the use of Mandala Gardens, Keyhole
Gardens and Herb Spirals contributed to the home gardeners food production
in Australia?"

My thoughts are that:

a) they may have stimulated interest in home and community gardening to some
(limited) extent

b) they may (I've got no figures... it's  only a guess) have stimulated some
gardeners to grow a greater diversity of crops in the home garden and to eat
mixed, nutritionally sound meals

c) I doubt whether they have contributed to higher productivity of home
gardening in Australia. The experiment conducted at Diggers Seeds and
described in their book "The Australian Vegetable Garden", wherein they grew
a year's supply of vegetables in a 42 square metre area (yes, rectangular
gardens), may have greater potential as a model for high-productivity home
and community gardens that mandala and keyhole gardens.

I think that it's not so much the shape of gardens that matter, it's the
conventional organic gardening methodology of soil management, irrigation,
closeness of planting, good seed and planting materials, management of
insect pests and disease and so on.

My understanding of these gardening things coming from permaculture is that
permaculture is organic gardening +  design. Thus, food production in
permaculture is based on organic gardening, of whatever type, and that
permaculture gardeners have a great deal to learn from organic gardeners.

Finally, I have seen the value of the 'keep it simple' approach so that
people can comprehend the principles of organic gardening... our approach to
teaching is that when people understand the principles they can interpret
them in different ways and produce different garden designs. That way, they
make fewer errors and have less chance to become discouraged.
 
>> Have they proved to be excellent concepts for selling books and courses and
> if so is this what we are deciding upon?

I think they are more than marketing ploys... that they were devised as
genuine attempts at solutions... but that they have too often become the
focus of the garden rather than more important things such as productivity
and so on.

...Russ Grayson