White Sweetclover
Melilotus alba

Also known as: Hubam

Summer annual legume


  • 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.

Cultural Traits

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


  • Planting depth: 1/4 - 1 inch
  • Inoculant Type: alfalfa, sweet clover

Seeding Method

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

Seed Cost: .70 $/lb

Seed Availability: Readily available


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


with small grains

Soil Improvements

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

Pest Control

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

Management Attributes

  • 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.


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 Sweet Clover (cv. 'Hubam'). Their specification describes Sweet Clover as follows:

  • 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.

For More Information

UC Davis On-line Cover Crop Index

Using clovers as living mulches to boost yields, suppress pests, and augment spiders in a broccoli agroecosystem by Cerruti Hooks, Raju Pandey, Marshall Johnson


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

Text last updated on 8/10/2007.

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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).