The COVER CROP
5 Steps for Deciding What to Plant When & WhereAdapted courtesy of Jason Lilley, Sustainable Ag Professional, U Maine Cooperative Extension
Late summer and fall are a good time to plant crops that provide winter cover, protecting and improving the soil for the following season. It's also the perfect time of year to implement a year-round cover crop plan, to enhance the sustainability of your operation on a broader, long-term scale.
Whether you're new to cover cropping or ready to take it to a whole new level, you may be wondering how to go about it. From tapping into the wisdom of your local growing community to a proliferation of online manuals, charts, graphs, and calculators, there are so many excellent resources to turn to.
To help you select the cover crops that are best for your unique farming needs, we've drawn on the expertise of Jason Lilley, our local Cooperative Extension Sustainable Agriculture Professional, and Eero Ruuttila, our Research Farm Manager. Here is how you can break the complexities of this whole process into 5 basic steps…
- Marianne Sarrantonio's Northeast Cover Crop Handbook is the best cover crop reference we've seen for the Northeast.
- Managing Cover Crops Profitably , a Sustainable Agriculture Research & Education (SARE) publication, is available online as a PDF as well as in hard copy .
- For a quick rundown of primary applications and benefits, see Top 10 Uses for Cover Crops & Farm Seed .
Most cover crops can serve more than one purpose — use the comparison charts and tools in the resources listed here to help you prioritize your goals.
Consider the following:
- What are the crops that have preceded the cover crop planting, and which ones will follow?
- How will the residue from the previous crop or the cover crop affect tillage?
- How will the weather at that time of year impact your efforts?
Refer to Crop Rotation on Organic Farms to design a rotation plan, incorporating cover crops into a longer-term rotation strategy.
Available planting and termination tools and equipment will have a bearing on which cover crops you can use. Similarly, equipment recommendations will depend on the cropping system you've elected. Basic equipment includes the following.
Cultivating baskets & Lely tines — being used to cover the broadcast oats.
Cultipacker — an essential farm implement for establishing small-seeded cover crops — shown cultipacking broadcast clover and oats. This year in particular, our new cultipacker has benefitted many different plantings of cover crop species as soil moisture has been very difficult to conserve.
Yeoman's plow. Used to prepare 1'-wide planting strips through crop residue in a strip-tillage system. It has a cutting disk for cutting through the crop residue, followed by the yeoman's shank that actually lifts the soil, followed by a beater basket that breaks up clumps. Planting is usually done in a separate pass. Soil can be prepared about 8" deep.
Field prepared for planting. Hairy vetch that was terminated with a roller-crimper seen in the foreground; rye terminated with a roller-crimper behind that; and vetch terminated by mowing. The rolled vetch took a little over a week to fully die.
In order to determine which cover crop species or mixes of species are going to work best for you, you must factor your location in to all of the above goals and challenges.
Use the following resources for guidance:
- The Midwest Cover Crop Council's Vegetable Cover Crop Decision Tool assists with comparing multiple criteria for species selection.
- The SARE Handbook, Managing Cover Crops Profitably comes in handy here as well, offering a wealth of information that can help you determine which cover crops are best suited to your region and operation.
- Talk to other growers in the region to learn what works for them — they may be able to share their experience, down to the level of specific cultivars, local microclimatic factors, weed and pest pressures.
- Of relevance to anyone practicing or interested in cover cropping, the Cover Crop Survey Analysis , conducted by USDA–NIFA and SARE (Sustainable Agriculture Research & Education), offers both broad perspective and detailed insight into how growers are using cover crops all across the U.S.
Once you've taken all of the above into consideration, chosen your cover crop species, and entered them into your multiyear rotation plan from Step 2 above, you're ready to put the plan in place.
- Record seeding rates, seed sources, weather, field conditions, and general observations.
- Use the Oregon State University Cover Crop Calculator for determining biomass and nitrogen credits from cover crops.
- Watch the benefits accrue!