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