Oilseed Radish is one of the newer additions to the cover crop market. It is best known for its deep tap root, quick emergence and rapid growth. It is primarily used to break up soil compaction, capture residual Nitrogen, suppress weeds, increase water infiltration, and increase soil biology.
Oilseed Radish has been divided in 4 'types' of which 2 are being used as cover crops, they are: Daikon, Forage, and Sugarbeet cyst nematode resistant. The Daikon is the most popular, due to its large taproot. The Forage type has lush top growth but a smaller and more branching root. The fodder from all types of radishes provides good forage, similar to turnips. It's best to plan a single grazing period, since it does not tolerate traffic well.
If seeded in late July to Mid August, root growth to a depth of 16+ inches is possible before a killing frost. Radish requires 8-10 weeks of 60 degree temperature to achieve optimum growth. The plant will die when temperatures reach 28 degrees F. After a killing frost the plant will decompose rapidly, leaving the ground bare by spring.
Radishes can be seeded alone or in combination with other seeds. The most common mixes include: winter peas, oats, annual ryegrass or cereal rye. Since radishes grow so fast, it's best to seed the various mixes by drilling in alternate rows. Also, since radishes decompose over winter, the addition of some of the grass species is recommended on the HEL soils for spring erosion control.
This is a picture of Enricher Radish and oats seeded early August.
This gives the benefit of the radish along with added bio mass
production of the oats, plus the added benefit of spring erosion
control. This mixture is ideal for the first time cover crop user
since they will die over winter.
This picture shows the competitiveness of
Enricher Radish in weed control. Note the weed
concentration in the wheel track vs the solid
stand. Weeds just can't compete in a good radish stand.
This is a picture of Enricher Radish and Austrian Winter Peas.
This is a popular mix that provides deep rooting and
compaction reduction along with significant Nitrogen
production for the following crops. For best results
drilling in individual rows is recommended. Be sure to
innoculate the peas.
Enricher Radish has excellent levels of glucosinalates. Glucosinalates is one of the mechanisms that radish uses to help control several nematode species. When planted with Bounty Annual Ryegrass, there is the double approach to controlling most nematodes including soybean cyst nematode. Annual ryegrass alone, when properly managed gives signifiact reduction in soybean cyst nematode and Bounty Annual Ryegrass has shown to be one of the best varieties of annual ryegrass for winter survival. The earlier one plants either or both cover crops, the better the chance one has of controlling the nematodes.
Enricher on the left, competitor on the right. Larger radish are Enricher, smaller
The radish were planted on 9/1/2010 in Effingham, IL. ones are a competitor under the same
August rainfall was .60", September 2.25" (most in growing conditions.
anyone rain was .50"), October .45" and November .80"
Seeding Date: Mid July to Aug 15
Seeding Rate: Drill - 8-12 lbs/ac
Broadcast - 15-18 lbs/ac
Seeding Depth: 1/4-1/2"
Note: Can be seeded in a mixture with cereal rye or annual ryegrass, which will add soil cover for spring erosion control after radish has decomposed.
Caution: After a killing frost and during decomposition the plants smell like rotting cabbage, which can be very offensive.
Management of Oilseed Radish and Yellow Mustard Green Manure Crop
Oilseed Radish: A new cover crop for Michigan
Midwest Cover Crop Council