Companion planting is the practice of grouping plants together that have beneficial relationships. Companion planting isn't an exact science, and takes experimentation and observation. The goal of companion planting is to increase the yield of plants by controlling for pests and encouraging pollination, whereas monoculture, or the practice of planting a single crop year after year, typically reduces the soil's nutrient levels over time.
A well-known example of this practice is the Three Sisters garden, consisting of corn, beans, and squash. Various Native American tribes discovered this practice thousands of years ago. These three crops work together symbiotically. The squash’s large leaves shade the ground and retain moisture in the soil. The corn provides a tall stalk for the bean vines to climb, and reduces weed competition on the ground.
Companion Planting with Vegetable Crops
Besides the Three Sisters, there are hundreds of beneficial crop combinations. Here's a quick summary of the main groupings:
Legume family plants, such as peas and beans, pair well with brassicas, carrots, lettuces, spinach, strawberries, corn, and cucumbers.
Brassicas, such as broccoli, cauliflower, and cabbage, can complement beans, carrots, lettuces, onions, spinach, and most types of herbs.
Alliums usually do well when planted with potatoes, carrots, lettuces, tomatoes, strawberries, and brassicas.
Place potatoes with onions, corn, lettuces, beans, and brassicas.
Lettuces and spinach both grow well with carrots, radishes, brassicas, onions, strawberries, and cucumbers.
Tomatoes love being paired with basil, nasturtiums, marigolds, onions, and cucumbers.
Most herbs can be placed together or among other vegetable crops.
Another aspect of companion planting is the placement of pest-repelling plants. Not all insects are harmful, but some can eat away your garden.
Some plants exhibit pest-repelling properties. Basil can avert whitefly when it’s planted among your tomatoes. Peppermint oil has been known to repel mice. (Be aware that mints are aggressive growers, though, and you may wish to confine their root systems to containers.) By masking the scent of carrots, strong-smelling alliums can deter carrot flies from your crop. Alliums have also been known to repel slugs.
You can also incorporate local, pollinator-friendly plants into your vegetable garden to support local pollinators, such as bees, butterflies, moths, and hummingbirds. Increasing the number of local pollinators in your garden will increase the yields from your vegetable-producing crops. Research which pollinator plants are native to your area. Otherwise, common options include purple coneflower (echinacea), yarrows, goldenrod, black-eyed Susan, salvias, penstemons, blanket flower, borage, and aster.
Temperature and Sunlight Variance
Cultivate crops that require similar temperatures and sun exposure together. Cool-weather crops, such as kale, lettuce, spinach, and broccoli, should be planted together in shadier areas that have lower temperatures. Warm-weather crops, such as peppers, tomatoes, zucchini, and squash, should be planted together in sunnier areas that have higher temperatures. Northern and eastern areas of a garden typically receive decreased sunlight and lower temperatures, while the southern and western areas typically receive increased sunlight and higher temperatures.
Krista Bratvold travels North America in her converted van to raise awareness for sustainable living and protection of our lands. She is a landscape photographer and travel writer who educates on sustainable food production and native plants. Connect with Krista at The Suitcase Photographers and on Instagram @thesuitcasephotographers. Read all of her MOTHER EARTH NEWS posts here.
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