Planting guide for using brassicas as a cover crop

Brassicas when planted correctly offer great benefits as a cover crop.

Brassicas are becoming a popular choice for those who are looking at new cover crop options. The benefits of brassicas are changing how we prioritize cover crop’s role in farming practices. Some of the attributes are:

  • Scavenger of nutrients
  • Weed suppression
  • Suppress soilborne pests
  • Alleviate soil compaction
  • Erosion prevention

Brassicas are not a substitute for your current pest control strategies. They can be a weapon in your fight against pests. Be advised that brassicas are a warm season crop and they need to be established in late summer or early fall. A major benefit to them is they do not handle our cold winters well, so most are winter killed.

The following planting guide is a chart of common brassica 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 in. Drilledlb./A.     Broadcastlb./A.    Aeriallb./A.       
Oilseed Radish 6.0-70 45 ½ - ¾ 10-20 11-22 12-24
Mustard 5.0-5.5 40 ¼ - ¾ 4-8 4.5-9 NR
Rapeseed/Canola 5.0-5.5 41 ¼ - ½ 2-5 2-5.5 2.5-6

NR - Not Recommended

Legumes and grasses 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 grossp@anr.msu.edu if you live on the east side of the state, Christina Curell curellc@anr.msu.edu if you live on the west and central part of the state, and Florian Chirra chirra.1@cfaes.osu.edu if you live in the southwest side of the state.

Did you find this article useful?