• Determine your goal: Each crop species has its own unique benefits and limitations. Therefore, it is important to select a crop that will contribute to your desired end goal. For example, for nitrogen enrichment, legumes like clover, peas or beans are ideal as they fix atmospheric nitrogen into the soil. For increasing organic matter, crops like oat, barley and rye are good choices because they have a high biomass. This resource outlines the typical characteristics of various cover crops. Additionally, when selecting a cover crop, consider how you plan on terminating the crop, as this will influence the equipment and time needed.  
• Consider timing carefully: Proper timing is important when implementing this restoration method. A suitable cover crop should fit within the planting and harvesting times of your main cash crop(s). Cover crops are typically sown before or after the main cash crop(s). Most crops need a minimum of two months to grow in order to deliver meaningful benefits to the ecosystem. The ideal time to terminate a cover crop is often in its flowering stage as this is the stage of peak biomass, but when the crop has not yet developed seeds, thus minimizing the risk of unwanted reseeding.
• Labour and equipment needs: Implementing cover crops involves additional logistics beyond typical crop production. Be sure to account for the equipment required for seeding and termination, as well as the labor involved in managing these operations.

Materials required:

1. Cover crop seeds of choice 
2. Preparing the soil for seeding (optional depending on the scale of operation)
   1. Rake
   2. Shovel
   3. Hoe
   4. Plough (for large-scale operations)
3. Seeding equipment of choice for seed distribution (optional)
4. Tools to terminate the cover crop (optional). Options for this range from low-cost manual methods to more expensive mechanised solutions  
   1. Mower
   2. Roller crimper
5. Irrigation tools (optional for small-scale operations)
   1. Drip irrigation
   2. Sprinklers

Steps of implementation:

After the crop species have been chosen, the following steps can be taken to implement cover cropping: 

• Prepare soil for cover crops: Start by removing all weeds, previous crops and debris to ensure good seed to soil contact for germination. This can be done using various tools such as a rake, shovel, hoe, or plough. Depending on the soil type and farm practices, tillage may be helpful, although this is not always necessary. 

• Seeding: Once the soil is prepared, plant the cover crop seeds according to the recommended depth and spacing for the crop. Use a method that fits your equipment and the scale of your operation. 

• Maintenance: As the cover crops begin to grow, monitor overall plant health. Look for signs of pests, disease, competition, and irrigation needs. 

• Crop termination: Before planting the main crop, ensure the cover crop is terminated at an ideal time that maximizes benefits whilst also fitting into the scheduled planting of the main cash crops. Termination techniques vary depending on the system and cover crop species, it may include natural winter-kill, mowing, tilling, roller crimping, and tarping. Ensure termination does not interfere with the planting and growth of the main cash crops. 

• Transition to main crop: After termination of the cover crop, prepare your field for your main crop by removing debris, applying fertilizer and tilling (optional). In this step, it is important to consider how cover crop residues will impact planting conditions like seed depth, spacing and nutrient availability for the main crop.

• Observation: During and after the main crop season, assess whether the cover cropping strategy helped to reach your goals. Keep detailed records to refine your cover cropping technique in the future. 

• • Note: some benefits like increased crop yields will only be realized after a number of years. 

Considerations for application:

• Additional production costs for seeds, labor and equipment may be required. 
• Cover crops can host pests and diseases which may impact the cash crops planted afterwards, so be sure to monitor the progress.
• If using legume species as cover crops, proper termination is essential to maximize nitrogen fixation in the soil. To optimize the amount of nitrogen being added to the soil, be sure to terminate legumes at peak biomass, ideally just before or during the flowering stage, when nitrogen accumulation is highest. Also ensure that roots are left in the soil, as this is where the nitrogen is stored. 
• Microorganisms in the soil need both carbon and nitrogen to grow and reproduce. Cover crops with a high carbon to nitrogen ratio such as oat, wheat and rye may cause microorganisms to use up nitrogen available in the soil, which can cause a shortage of nitrogen for young cash crops. Make sure carbon and nitrogen levels in the soil are balanced before planting the cash crops.

This intervention contributes to:

Costs will vary greatly depending on location, management, and crops grown. However, this online tool can help explore the potential financial impacts of implementing cover crops for your specific scenario.  

In the table below, the results from a study in which direct expenses of 132 farms in Minnesota and Wisconsin were analysed to provide cost estimates for this intervention. 

1. Cover cropping on a no-till farm in Wisconsin

Gary Sommers operates a no-till 1,500-acre farm in Clinton, Wisconsin where he rotates between corn, soybeans and wheat as his primary cash crops. After the harvest of wheat, various cover crops are grown such as oats, soybean, buckwheat, and Berseem clover to reduce soil erosion. To ensure timely planting for corn in the spring, the cover crops that do not die off in winter are terminated. 

One technique utilised on the farm is the mixing of red clover seeds in with the fertiliser applied in early spring. The seeds then fall into cracks created as the ground freezes and thaws. This method is efficient as it does not require additional labour or fuel, and the clover can grow after the wheat without reducing the yield of wheat. This process decreases the amount of nitrogen input needed for growing the corn in the following year. One drawback of this method is that it can obstruct the baling of wheat straw.

2. North Dakota Ranch 

After a series of hailstorms and drought that destroyed the main crop of this conventional farm in North Dakota, serious changes were needed to restore his land. More regenerative agriculture practices were implemented in response, focusing on rebuilding soil health and system resilience. They began utilising a cover crop mix of about 25 different species. After 20 years of applying this method, the soil organic matter went from ~ 1.8% to ~ 7%. Additionally, the infiltration rate of the soil was increased, thus rainfall was able to better penetrate the soil instead of contributing to runoff. Overall, these changes helped to create a more resilient and productive farming system, better equipped to handle environmental stressors in the future.

Webinars

• Cover Crop Basics

External sources

• Cover crops on your farm

• Past, present, and future of the cover crop industry

• Building better soils for better crops: Cover crops 

• Cover Crop Termination

Guides

• Extensive Cover Crop Guide

• Interactive cover cropping guide

Videos

• Cover Cropping for Soil Health

• How to choose the right cover crops for what you need