Planting guide for using legumes as a cover crop
Legumes are a great cover crop choice the key is to plant them correctly.
Legumes used as cover crops offer many benefits to a farm system. Legumes can be winter annuals, summer annuals, perennial or biennial. Some of the advantages or legumes are:
- Fix nitrogen from the air which can be used by the following crop
- Erosion prevention or reduction
- Biomass production
- Add organic matter to the soil
- Attracts beneficial insects
- Breaks down faster than grasses because legumes have a lower C:N ratio
The following planting guide is a chart of common legume cover crop species used in Michigan. For more in depth information on specific species, consult your Michigan State University Extension educator. A recommended resource for incorporating cover crops into a cropping plan titled “Managing Cover Crops Profitably” is available from SARE.
|Species||Soil pH||Min.Germ.||Depth ininches||Frost seed||Drilledlb./A||Broadcastlb./A||Aeriallb./A|
|Alfalfa Dormant||6.0-8.0||34F||¼ - ½||No||12-16||13-18||NR|
|Alfalfa Non-dormant||6.0-8.0||34F||¼ - ½||No||12-16||13-18||NR|
|Red Clover||6.2-7.0||41F||¼ - ½||Yes||8-12||9-13||9.5-14|
|Crimson Clover||5.5-7.0||42F||¼ - ½||No||10-15||11-17||12-18|
|Peas Field/Winter||6.0-7.0||41F||1-1 ½||No||60-90||65-100||NR|
|Sweetclover||6.5-7.5||42F||¼ - ½||Yes||6-10||6.5-11||7-12|
|Hairy Vetch||5.5-7.5||60F||1-1 ½||No||15-25||17-28||18-30|
NR- Not recommended
Grasses and brassicas also have many benefits. Research has shown that growers who use mixes of two or more cover crops from different families can get the benefits from both of the families. It is however important to prioritize what your objectives are for the cover crop before you purchase seed. Species within a family will have different degrees of an attribute. MSU Extension cover crop educators can help you determine what your objectives are and to choose a cover crop specie or mixture that would best suite your needs. In Michigan you can contact Paul Gross at firstname.lastname@example.org if you live on the east side of the state, Christina Curell email@example.com if you live on the west or central part of the state and Florian Chirra firstname.lastname@example.org if you live in the southwest side of the state.