Vigna unguiculata

Also known as: blackeyed peas, southern peas

Subtropical and tropical annual legume


  • Nitrogen source (100-150 lb. N/ac)
  • Biomass/organic matter source (Dry Matter: 2,500-4,500 lbs/ac/yr)
  • Weed suppression
  • Insectary plant
  • Companion crop in orchards, vineyards, corn
  • Drought tolerant
  • Food, seed, forage, or hay crop

Plant Highlights

  • EXCELLENT for providing erosion control, for suppressing weeds
  • VERY GOOD for quick growth and establishment
  • GOOD for increasing organic matter and improving soil structure, for animal grazing (production, nutritional quality & palatability)
  • FAIR for taking up & storing excess N, for providing lasting residue.

Cultural Traits

  • Excellent heat tolerance
  • Very good drought tolerance
  • Good shade tolerance
  • Fair flood tolerance
  • Excellent tolerance to low fertility
  • pH range 5.5-6.5


  • Planting depth: 1 - 11/2 inches
  • Inoculant Type: cowpeas, lespedeza

Seeding Method

  • Drilled: Seed at 30-90 lb./A
  • Broadcast: Seed at 70-120 lb./A

Seed Cost: .50 $/lb

Seed Availability: Readily available


Cultivars commonly recommended by the Hawai`i Natural Resources Conservation Service include: 'Mississippi Pinkeye Purple Hull' which is reported to be root knot nematode resistant, burrowing nematode susceptible.


with sorghum-sudangrass hybrid, buckwheat

Soil Improvements

  • Good for loosening subsoil
  • Good at releasing P and K
  • Very good at loosening topsoil

Pest Control

  • Poor for suppressing nematodes
  • Poor for disease suppression
  • Poor allelopathic properties
  • Excellent weed suppression
  • Very good for attracting beneficial insects

Management Attributes

  • Poor trafficability
  • Rapid establishment and growth ideal for short windows


  • Cowpeas germinate quickly and are easy to establish. They thrive in hot moist climates.
  • To control disease and nematode problems, cowpeas should be rotated with four to five years of crops that are not hosts.
  • Once cowpeas form pods, they may attract stinkbugs. Flail mowing or incorporating cowpeas at pod set or plan crop rotations with resistant crops.
  • Cowpeas survive drought well once established.
  • Mowing stops vegetative growth but may not kill plants without shallow tilling.
  • Cowpeas have extrafloral nectaries that attract beneficial insects such as wasps, honeybees, lady beetles, ants and soft-winged beetles.

Uses in the Pacific Region

No information is available in this database on this topic.

Uses in Hawai'i

The Hawai`i Natural Resources Conservation Service Technical Guide includes Cowpea (cv. 'Mississippi Pinkeye Purple Hull'). Their specification describes Cowpea as follows:

  • Minimum broadcast seeding rates of 60 lbs. pure live seed/acre;
  • pH range from 5.5-8.3;
  • Inoculant group: cowpea;
  • Approximate growing time 90 days;
  • Approximate dry matter yield 2 tons/acre;
  • Approximate N content 59 lbs./T dry matter;
  • Optimum planting period year round at elevations from 0-1000 ft.;
  • Optimum planting period spring/summer at elevations from 0-2000 ft.

For More information

UC Davis On-line Cover Crop Index

FAO Web Site


1998. Managing Cover Crops Profitably, 2nd ed. Sustainable Agriculture Network, National Agricultural Library, Beltsville, USA. pp. 212.

USDA Natural Resources Conservation Service, Hawai`i Field Office Technical Guide, Section IV, Code 340 "Cover and Green Manure Crop" May 1992. Pacific Islands Area Field Office Technical Guide (eFOTG) - East Area

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These webpages were originally generated under a grant program from Western SARE entitled "Covering New Ground: Tropical Cover Crops for Improving Soil Quality" EW98-012 (1998-2002).