A Model for Companion Planting and Crop Rotation

Companion planting is a practice of applying different plant species in close proximity so that they can offer identifiable benefits to each other. Some of these benefits include improved soil health, pest and weed control, increased yields, and enhanced pollination.  Examples are the three sisters: corn, beans, and squash; sunflowers, cucumbers; pole beans; basil and tomatoes; and sage, carrots, or cabbage.

Crop rotation is the practice of not planting the same crops in the same place in back-to-back years.  By rotating crops, one can improve soil fertility, break pest and disease cycles, and reduce the need for herbicides and pesticides. 

Here is a model of three- or four-year rotations of companion plants.

• One year, Legumes, (legumes fix atmospheric nitrogen, increasing soil nitrogen levels),  including beans, peas, and edamame
• Followed by Leaves, including lettuce, green spinach, and kale crops
• Followed by Fruits, including tomato, cucumber, pepper, and corn
• Followed by Roots, including onion, garlic, carrot, and beets
• Repeat

Vegetables belonging to the same botanical family are susceptible to the same issues and diseases. Therefore, it is advisable to follow members of one family with those of a different family. Alternate heavy feeders, such as corn, tomatoes, lettuce, and kale, which require a significant amount of nitrogen, with light feeders like carrots, potatoes, beets, and onions to minimize nutrient demands on the soil.

For legumes, it is recommended not to remove these plants in the fall but rather to clip them off and allow the roots to decompose in the soil. This process will create nitrogen accessible to next year’s plants.