"terryc" wrote in message
news
On Tue, 06 May 2008 00:26:00 +0000, 0tterbot wrote:

have realised what my problem is re rotating the garden beds in an
organised
manner:

It is a worry here as well as we tend to grow mixed beds and sometimes
they evolve rather than follow the strict idea of wipe clean and replant.

The real problem is that multiple plantings of the same crop(famil) in
the same plot allows pests/dieseases to buld up in that spot. so
spelling the ground from that family lets them starve away.

all you can really do is rotate different plots in turn from that family
until the family fad fades {:-).

I have pondered rotation myself. Having only been growing in this garden for
the last few seasons so I have only just started getting it straight mind.

I have 5 gardens, 3 long rectangular ones, a shorter squarish one and a
triangle shaped one. For my major crops I reckon I can do a 3 year rotation.

By major crops I mean tomatos, sweet corn and kumara over summer. In one
year I grew potatos but switched to kumara this year & reckon I may continue
with that. I plan to grow those 3 major summer crops again next summer.
Rotating will have tomatos back in the same bed on the fourth year of a
cycle.

year one tomatos
year two kumara
year 3 sweet corn
year 4 tomatos

lettuces, broccoli, beetroot, spring onions etc get grown in the 2 smaller
beds and at the end of rows of the big 3 crops as space allows.

This all changes over winter.
The triangle bed mostly gets rested over winter as it does not get winter
sun.
Of the 3 big crops, I have figured out that garlic is quite a good one to
follow tomatos. The tomato bed will be cropped heavily with garlic until
early summer. One winter I followed the tomatos with a mustard green manure.
I have undersowed a green manure of beans under the sweet corn. The kumara
bed has been stripped out and will have some broccoli, beetroot & lettuces.

I am happy with the big 3 crop rotation, though maybe sweet corn should
follow tomatos and then followed by kumara. Not sure yet of the nutrition
requirements. The text book rotation I came across recently is apparently a
nitrogen green manure (like beans), a leaf vegetable, a seed/fruit (like
tomatos or corn) crop and finally a tuber crop. I guess I would need 4 large
garden beds for that.

A mate who is an organic grower told me not to be anal about rotation, given
the size of my back yard vege garden. Mr Yates points out that in temperate
climates there is a natural rotation between hot season & cool season crops.
You can't follow egg plant with tomatos or follow tomatos with potatos. He
also suggests gardens packed with organic matter, humus, compost etc help
minimise build up of problems in garden beds (maybe the microbal activity in
the humus combats negative soil deseases etc). Feeding the garden with poop
or compost each year also minimises the need to sow nitrogen fixing or
nutrient scavaging green manures.

That said, I reckon green manures are quite an interesting topic & something
I am starting to get my head around. The beans are an experiment with
nitrogen fixers (I don't eat beans). The mustard was an experiment with keep
the bed covered over winter & stopping nutrients leaching. I guess if you
are going to fallow a garden for a season or 2 a green manure makes sense
for a number of reasons. The organic grower mates suggested with nitrogen
fixers also putting in something that will use the nitrogen, maybe a grass.
A 1/2 clover & grass mix on a garden bed will get the clover producing
nitrogen and also have a crop that utilises the nitrogen, thereby
encouraging the clover to produce more nitrogen. When the crop is killed and
mulched you get double the amount of nitrogen being returned to the soil
(what the clover produced & what the grass took up).

rob