When should I terminate cover crops?
Written by
Tina Carter
Reviewed by
Prof. Samuel Fitzgerald, Ph.D.Ending the cover-crop at the right time to maximize advantages and avoid competition with your cash crops. Good timing allows nutrients to release slowly and enables residue to protect the soil, without impeding planting. I've learned from working in this area that this step is one of the primary components that drive overall success with a cover crop system.
Nutrient Release Planning
- Terminate 3-4 weeks before planting for complete biomass decomposition
- Allows nitrogen fixation from legumes to become plant-available
- Ensures gradual nutrient release matches cash crop needs
Moisture Management
- Prevent competition during cash crop germination and establishment
- Allows soil moisture recharge before planting main crops
- Residue mulch conserves water without competing with roots
Equipment Compatibility
- Ensure residue breaks down enough for smooth planting operations
- Prevent wrapping on planter disks or seeding mechanisms
- Adjust termination method based on equipment capabilities
Termination before seed set helps to avoid unwanted volunteers. Cover crops, such as rye, will become weeds if allowed to seed. I terminate at flowering. Then, your cash crops grow without pressure from the last cover crop.
The timing of decomposition plays a huge role in nutrient supply. Terminate cover crops before planting, allowing enough time for microbes to break down. I give some vetch and rye 3 to 4 weeks to break down. This breaks down nitrogen and other nutrients at the time your cash crops need nutrients the most.
When planning termination, consider the weather. For instance, dry springs require prompt termination to retain moisture. In contrast, wet springs might require delaying termination to help improve soil compaction. The local circumstances will vary, and the specifics of timing will depend on achieving the best possible outcome.
Start with easy-to-manage crops, such as oats, that die naturally in the winter before moving on to rye once you are becoming comfortable with the termination methods. Your confidence will develop as you see improved soil and improved establishment of cash crops.
Read the full article: Cover Cropping Benefits for Sustainable Farming
