The Inspector’s Notebook #9
Planning the perfect rotation: Three part series on creating crop rotations

Part 2: A good transition provides the ground work for fields that are nutrient stable, disease free and haven’t washed into the local river. These ten easy rules will give you a head start then keep you running ahead of the pests.

By Jim Riddle

Editor’s NOTE:

Certified organic farmers do an odd thing – they pay people to visit their farms with a critical eye to assure they are adhering to every aspect of the USDA’s national organic standard.

The farmers should already be trying to produce, harvest and market their organic crops, livestock and related products by these rules. The on-farm review of fields, facilities and records by an approved inspector sent by the farmer’s accredited organic certifier is the critical point in confirming that the farmer and the farm meet the organic standards – and can prove it to anyone who needs to know.

The visits are pivotal for applying farmers to become certified, and for certified farmers to keep that certification. For the good of organics, we want to help build the foundation for effective inspection visits. We’ve asked Jim Riddle to provide an inspector’s inside view to help farmers understand an inspector’s role, responsibilities and limitations.

In the months ahead, Riddle will elaborate on many items to help farmers understand regulations that apply to them, and how to document their compliance.

Jim Riddle has been on hundreds of farms in the inspector role, and he’s been inspected himself during his time as a farmer. His leadership in bringing professional training to inspectors helped to earn greater acceptance of organic farming in the U.S. He serves as vice-chair of the National Organic Standards Board, which advises the USDA on organic agriculture policies and regulations. He has been an organic farmer, gardener, inspector, educator, policy analyst, author, and consumer.

Jim Riddle serves as vice-chair of the USDA’s National Organic Standards Board and organic policy advisor for He was the founding chair of the Independent Organic Inspectors Association (IOIA).

January 27, 2005: I see a lot of good examples of crop rotations on the farms I inspect. The best rotations are the ones designed to meet the objectives described in my previous article including improving soil, providing nutrients to the plant and erosion control.

For your information...
The National Organic Program defines crop rotation as “the practice of alternating the annual crops grown on a specific field in a planned pattern or sequence so that crops of the same species or family are not grown repeatedly without interruption on the same field."

Rotation planning and implementation should begin during the transition period from conventional to organic. During transition, you should use your crop rotation to build fertility, break pest, weed and disease cycles, and prevent soil erosion. It is also a good time to experiment with different rotational crops to find out which ones work best on your farm.

In addition to the issues discussed in Part 1, factors to consider when designing your crop rotation include:

  • Cropping history – transition using pasture, hay, legumes, or smother crops; do not use heavy feeders such as corn, grains, or vegetables
  • Soil building – use legumes and grasses; try intercropping; watch organic matter and microbial activity
  • Conserve nutrients – keep in mind catch crops, cover crops and plow-downs
  • Erosion control – cover crops are key, also, soil structure, aeration, moisture retention and filtration of runoff
  • Weed suppression – try smother crops, allelopathic crops, mowed or grazed crops
  • Pest control – pest resistant crops, intercropping, strip cropping and companion plants work well; avoid alternate hosts but provide habitat for beneficials and pollinators
  • Disease management – break disease cycles by selecting resistant varieties, using disease suppressing plow-downs and alternating crop families
  • Maximize use of on-farm resources – including seeds, equipment, labor, knowledge, timing and nutrient cycling
  • Crop value – don’t forget markets, contracts, livestock feed, seed needs and quality demands
  • Impact on subsequent crops – inhibit seed germination, ease of incorporation, impact on nutrient availability to digest crop residues with high carbon content

When introducing new crops into a rotation, experiment with the new crops on a limited scale--make sure that they fit into your system before “betting the whole farm.”

Here are a couple of excellent options to consider working into your rotation. Winter rye grain (not the same as ryegrass) planted after crop harvest is a great way to improve soil organic matter content, manage deficient or excess plant nutrients, suppress weeds, and provide erosion control. Rye will even germinate after frost. When used as a plow-down in the spring, rye has an allelopathic effect on annual weeds. On our farm, we always plant rye mixed with hairy vetch as a winter cover crop. The vetch adds nitrogen.

Buckwheat is an excellent choice for summer plantings, especially for vegetable growers. Planted in warm soil, buckwheat germinates and grows rapidly, helping to control thistles and other weeds. Buckwheat also improves soil fertility by accumulating phosphorus, potassium and calcium and helping to make these and other nutrients available to the following crop. To avoid problems with volunteer buckwheat appearing later as a “weed”, it should be tilled in before it forms viable seeds (about 4-6 weeks after planting).

In the concluding article in this series, I will present steps to follow to design your crop rotation plan and give examples of crop rotations for various types of farming operations. Stay tuned…