Cascadian Farm Organic | Our Farm | Farm Blog | Cover Crops
Cover Crops: What Are They and Why Are They Important?

Cover crops are plants intentionally grown on the land, for the land when it is not growing a cash crop for future sale. Cover crops are worked back into the soil to provide multiple benefits to future crops.

Why are they important?

  • Cover crops are a valuable resource to maintain and improve the fertility of the soil. Soil is formed through the weathering of parent rocks and minerals into sand, silt, and clay. The real magic starts when plants grow, die, decompose, and  blend with the soil minerals creating a living soil with a complex internal “soil food web”. In nature, bare earth is quickly covered with a variety of plants that sprout from seeds and root material in the soil. You can observe this after a forest fire, land slide, or clearing of the vacant lot down the way. This quick colonization of plants protects the soil from erosion and compaction during rain.

 

Why are they important to organic farming?

  • Organic farming is farming in harmony with nature. Understanding the way nature builds soil, organic farmers select specific crops to use as cover crops to achieve specific results. Using knowledge gained through scientific discovery, we can build soil. Some examples are:
    • Grain crops and other grasses can be used to scavenge excess nitrogen and other elements from the soil and prevent them from leaching into and polluting the ground water. They also create organic matter which will decompose and build the soil.
    • Legume crops (the bean and pea family) partner with rhizobia bacteria in the soil and pull nitrogen out of the air and store it in the plant.  This added nitrogen will become available to following crops as it decomposes and moves through the soil food web.
    • Cover crops can be grown at different times in a crop rotation program to achieve specific goals such as weed suppression or attracting pollinators and other beneficial insects.

 

When’s the best time to plant them?

  • It depends on the desired result and your specific climate when cover crops should be planted. For weed suppression you want to plant well ahead of the natural germination time of the weeds you are suppressing so your cover crop is nice and thick and will shade out and kill the weed seeds as they germinate.
  • To attract beneficial insects, you need to plant the cover crops early enough to have attractive blooms at the time you will need the beneficial insects moving onto your land.

 

What are some examples of good cover crops?

  • Your climate and your specific cover cropping goals are key factors in choosing the cover crops that are right for you. Grasses (including grain crops) scavenge nutrients and produce a lot of organic matter. Legumes add nitrogen and during bloom will attract pollinators and other beneficial insects
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