Our
Mailbox: Organic Crop Rotation.
Q.
My wife and I had a great time being first time customers of your farm.
We are now enjoying several varieties of potato that we could not have
otherwise.
We are starting to plan our garden for
next year and have read a little about crop rotation regarding
potatoes. Could you offer any advice or guidelines regarding potato
planting rotations? Thank you,
GS
Sykesville MD
A.
Crop rotation is absolutely one of
the most important practices for an organic gardener or farmer.
A
good rotation helps break up insect and
disease cycles, facilitates nutrient cycling and protects the soil.
In simplest concept, an organic crop
rotation means crop relocation: not planting the same crop (for
example,
potatoes) or family (nightshades which include potatoes,
tomatoes,
peppers and eggplant) in the same spot for two years in a row.
Among the crops that can
precede potatoes are squash, corn or the members of the Brassica family.
If
your land base is sufficient to allow the
soil to rest, sod or other soil-building cover crops can build
fertility, soil
tilth and organic matter and are highly recommended. But even the
simple sowing of
a fast growing grass (like
Annual
Rye) or grain (like
Oats
or
Wheat
or
Winter
Rye or
Buckwheat,
or
Winter
Triticale) on a plot as soon as
it is harvested will minimize erosion, catch nutrients for succeeding
crops, and add organic
matter.
Going back more than one hundred
years the traditional potato rotation here in Aroostook County was a
five year
potato rotation: two years of potatoes, followed by a year of oats and
two
years of clover and timothy sod. We created our four year Wood Prairie
Farm organic
rotation by
modifying the traditional: Year one:
Seed
Potatoes; Year two: Spring Grain
(wheat or oats) nurse crop over clover-timothy underseeding; Year
three:
Clover
and
Timothy
sod; Year four: plowdown
Buckwheat
cover crop followed by plowdown biofumigant
crop Dwarf Essex Rapeseed; Year five back to seed potatoes. So, each of
our
fields sees potatoes just once every four years. By rotating our
fields,
in any
given year, we have one quarter of our cropland planted to potatoes,
another
quarter planted to Spring grains and the last half in sod and cover
crops that build the
soil up for the next seed potato crop. A well-designed crop rotation on
organic
farms will often have half of the cropland in soil building cover
crops. We
believe that our relatively long rotation is a significant factor in
the high
quality of the organic seed potatoes we grow.
There are excellent books out there
that delve into good explanations of organic crop rotation
considerations. Two
of the best are Eliot Coleman’s
The New
Organic Grower and John
Jeavon's
How
To Grow More Vegetables and Fruits.
And
here’s another great in-depth
book entitled
Crop
Rotation on Organic
Farms – A Planning Manual
(NRAES
Publication 177). The effort behind this recently published book began
about
ten years ago when experienced organic vegetable farmers from Maine to
Maryland
were brought together by a USDA funded project called Northeast Organic
Network
(NEON). Our mission was to discuss, formulate, critique and catalog
important
organic crop rotation details and document working examples.
You’ll find
our Wood Prairie Farm rotation included on page 52.
When it
comes to subject depth we've found that single topic farm books
(‘Potatoes’,
‘Blueberries’) hit the mark. You won’t be
disappointed with this landmark
158 page manual. It is a book you’ll want to add to your farm
library. By going
to
this
link
you may either purchase the printed book for $24 or review and/or
download the entire book for
FREE.
Now that’s a deal!
Jim