Green Manure Cover Crop Mixture
Our Green Manure Cover Crop mix can be used as a late-season, winter cover crop or a short-lived spring cover crop, that will provide vigorous growth to loosen the soil and improve drainage, provide winter erosion control and add vital nitrogen, nutrients, and organic matter to enrich and build the soil and control weeds.
Plant this mix as a cover crop in orchards and vineyards or in rotation with vegetable and field crops in early spring or from mid-September to October (15-45 days before first frost) to get established before freezing temperatures arrive. The vetches are also excellent pollinator plants, attracting honeybees and beneficial predatory wasps.
Sow the Green Manure Cover Crop mix at a rate of about 1 pound per 500 sq feet, about 50 days before the first killing frost. The winter rye and oats will grow over the winter even when the temperatures are barely above freezing and form a thick tangle of roots and tough stalks that add fibrous organic matter to the soil. The vetches and Austrian Peas are also winter-hardy and are prolific nitrogen producers, so you’ll need less fertilizer.
This ‘green manure’ should be mowed or incorporated (tilled under) after flowering, before seed production if you don’t want volunteers sprouting up next season. Till under about 1 month before you plan on planting your crops.
Green Manure Cover Crop Mix Seeding Tips:
Contents: (inoculated) Percent Nitrogen accruement*
Austrian Winter Peas Pisum sativum subsp. arvense 30% 3.3 lbs/1000 sq. ft.
Winter Hairy Vetch Vicia villosa 15% 3.2 lbs./1000 sq. ft.
Common Vetch Vicia sativa 25% 1-2 lbs /1000 sq. ft.
Oats Avena sativa 15% 2 lbs /1000 sq. ft.
Winter (annual)Rye Secale cereale 15% 2 lbs./1000 sq. ft.
* Nitrogen accumulated in growing crop prior to tilling under
Seeding Rate: 5lbs./2500 sq. ft. or 1lb./500 sq. ft.
Find more information in our post about Why You Need to Plant Cover Crops.
Learn more about Cover Crops from the Colorado State University Extension Service.
Cover Crops are a great way to improve your garden’s soil and they are one of the easiest ways to start a new garden bed. This video from “Gardens That Matter” explains the basics (the why, when, and how) of cover crops.
“When fresh plant material decomposes in the soil, its carbon-to-nitrogen ratio becomes low, allowing the nitrogen to be easily released into the soil chemistry by bacteria. Nitrogen accumulation is greater with legumes, which have nitrogen-fixing Rhizobium bacteria growing in nodules on the legume roots.
Microorganisms decompose plant material and the plant material itself produces substances that glue soil particles together. These substances include slime, mucus, and fungal mycelia, which contain gums, waxes, and resins. They aggregate soil particles, thereby enhancing the tilth, porosity, and water holding capabilities of the soil.”