• Nitrogen source (70-90 lb. N/ac)
  
• Biomass/organic matter source (Dry Matter: 4,000-5,000 lbs/ac/yr)
  
• Nutrient scavenger
  
• Improve soil structure
  
• Alleviate soil compaction (deep taproot)
  
• Attract beneficial insects
  
• Drought tolerant
  
• Grazed pasture, forage, or hay crop
  
  

Plant Highlights

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

• Very good heat tolerance
  
• Excellent drought tolerance
  
• Fair shade tolerance
  
• Fair flood tolerance
  
• Excellent tolerance to low fertility
  
• pH range 6.5-7.5
  
  

• Drilled: Seed at 6-10 lb./A
  
• Broadcast: Seed at 15-30 lb./A
  

• Cultivars commonly recommended by the Hawai`i Natural Resources Conservation Service include: ‘Hubam’.
  
  

• Excellent for loosening subsoil
  
• Excellent at releasing P and K
  
• Excellent at loosening topsoil
  
  

• Fair for suppressing nematodes
  
• Fair for disease suppression
  
• Fair allelopathic properties
  
• Good weed suppression
  
• Very good for attracting beneficial insects
  
  

• Good trafficability
  
• Slow establishment and growth
  
  

• Seeding too deeply is a common cause of poor establishment.
  
• Weed management may be required during establishment.
  
• Sweetclover is reported to be able to extract K, P and other nutrients from the subsoil.
  
• Its deep taproot can combat compaction.
  
• Once established, it is very drought tolerant.
  
• Sweetclover blossoms attract honey bees, tachinid flies and large predatory wasps.
  
  

• Minimum broadcast seeding rates of 20 lbs. pure live seed/acre;
  
• pH range from 6.0-8.0;
  
• Inoculant group: clover;
  
• Approximate growing time 90 days;
  
• Approximate dry matter yield 2.5 tons/acre;
  
• Approximate N content 63 lbs./T dry matter;
  
• Optimum planting period year round at elevations from 0-2500 ft.
  
  

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

Online excerpts: http://www.sare.org/mccp2/

USDA Natural Resources Conservation Service, Hawai`i Field Office Technical Guide, Section IV, Code 340 "Cover and Green Manure Crop" May 1992.

If you have used this plant as a green manure in the Pacific Region, please email us with COMMENTS and FEEDBACK about this plant description so we can continue to refine this educational resource.