permaculture

[Robyn Francis <erda@nor.com.au>]

I have heavy clay soil and major drainage issues during our wet seasons when
we can get up to 1700mm (approx 70 inches) of rainfall. As I already have a
lot of land under water with ponds and dams I wasn't needing or wanting more
water bodies with a traditional-style Chinampa but adapted the Chinampa
principle. I built meter-wide drains about 30-40cm deep (to the base of the
top soil) in sections of the garden, used the topsoil to build up the beds
and use the drains for wetland taro production. The system works
exceptionally well.
Some of the issues for me re creating a full-blown Chinampa system was loss
of production space in an intensive garden zone - chinampas to work need to
be approx 20-30 wide and deep enough to create a productive water body if
aquatic animals are going to be included. This would have meant a lot of
clay excavation (and the issue of what to do with it) and cost. Also for 8
months of the year the water areas would be dry and pose management issues.

What's important is to understand the principles and reasoning behind
systems and then adapt them according to the situation, context, scale etc.

Ciao

Robyn


On 11/1/07 11:28 AM, "Keith Johnson" <keithdj@mindspring.com> wrote:

> We could probably do a modified mini-chinampa system here in Indiana
> with our poor draining clay soils (or anywhere with similar soils and
> 36+ inches of rain) and we could keep them filled with overflow from our
> rainwater tanks and some greywater. Anyplace wet or boggy could be
> suitable. People should DO these! They work great. Be sure to design for
> flood periods.
>