Vigna subterranea
Plant Family
Fabaceae
Binomial Name, Author
Vigna subterranea (L.) Verdc.
Synonymous Binomial Names
Arachis africana, Glycine subterranean, Voandzeia subterranean (L.) thousars
Common (Vernacular) Names
Bambara groundnut, Bambara nut, groundnut, Bambara beans, earth pea, hog-peanut, Congo goober, Jugo beans (South Africa), Ntoyo cibemba (Republic of Zambia), Gurjiya or Kwaruru (Hausa, Nigeria), Okpa (Ibo, Nigeria), Epa-Roro (Yoruba, Nigeria) and Nyimo beans (Zimbabwe); Izindlubu in isiZulu, South Africa (Mahbudhi et al. 2013; Bamshaiye et al., 2011; et al.)
Plant Characteristics
Endemicity. Groundnuts are endemic to West Africa.
Growth Habit. A small herbaceous annual legume plant about 0.3 m (1 foot) tall with creeping stems at ground level. Its stems emerge from a crown on the soil surface, each with one compound leaf consisting of three leaflets.
 Vigna subterranea Seedling |
 Potted Bambara Groundnut Plant
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Flowers. The small, pale yellow flowers form on freely branching stems under the foliage at the base of the plant. After pollination these grow as ‘pegs’ down into the soil.
 Vigna subterranea Flower Close Up |
 Flowers of Bambara Groundnut Under Plant |
Seeds. The seeds (groundnuts) form in pods that ripen below the soil surface like peanuts. The round, wrinkled pods contain one or two seeds that become very hard after drying. The seeds have several different colored varieties.
 Large Yellow Bambara Groundnuts |
 Red Bambara Groundnuts |
 Bambara Groundnuts, Assorted Colors |
Uses
Bambara groundnut is an indigenous African legume. It is the third most important legume in terms of consumption and socioeconomic impact in semi-arid Africa behind peanuts (Arachis hypogaea) and cowpeas (Vigna unguiculata). The seeds are highly nutritious and have been described as a complete food.
Human Food. Groundnuts can be consumed fresh or boiled after drying, and can be ground either fresh or dry to make flour and puddings. A recent news story on CNN (Cairns 2022) reported new and innovative uses of groundnut flour in making instant noodles, soups and shakes. These new, potentially large scale uses are likely to incentivize increasing production.
Livestock Feed. Groundnuts are used for fodder and livestock feed.
Intercropping. Groundnuts have been used for intercropping with a wide variety of other crops and as companion plants for crop rotation.
Traditional Medicinal Uses. Groundnuts have several traditional medicinal uses and they are reported to have antimicrobial activity against Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, Escherichia coli, Bacillus cereus, Candida albicans (yeast) and Aspergillus niger (mold) (Olanrewaju et al. 2022)
Research Interests. We are encouraging investigation of groundnuts as a potential crop in the United States. This effort will include introducting it to Hawai`i farmers and we hope to start some small field trials here in the near future. It may also have potential use as a nitrogen fixing ground cover crop for agroforestry applications with moringa.
Cultivation
Groundnuts are primarily grown in the semi-arid areas of Africa. A secondary growing area exists in South East Asia, particularly Indonesia, Malaysia and Thailand.
They are nitrogen fixing legumes and capable of growing on nutrient poor soils that may not support other crops. The cycle of growth from seed planting to harvest is 90-120 days.
Cultivation in the United States. Groundnuts have apparently not been grown as a crop in the U.S. In 2020 the Utopian Seed Project started a small field trial in Western North Carolina (USP 2022) but the results of the trial are unknown. With the emergence of more arid conditions in many areas of the country groundnuts could provide an alternative crop for these areas.
Cultivation in Hawai`i. The Herbarium Pacificum (Bishop Museum) has a specimen of this plant collected in 1942. The record indicates that is was grown in Kailua and Waipio. We were unable to find any additional references indicating that this species has been grown as a crop in Hawai`i.
Taro is an important crop in Hawai`i. Mabhaudhi (2013) investigated intercropping taro and bambara groundnut and concluded that intercropping at a ratio of 1:1 is feasible and productive under rainfed conditions. This practice would allow farmers to mimic historical diversity that existed in traditional agroecosystems.
Propagation
Seeds. Groundnuts are grown from seed.
We generally do not recommend the use of groundnuts imported into the United States under food commodity rules for planting. These may not be subject to thorough inspections or have the phytosanitary certifications required for propagative plant materials. Food safety regulations may allow for some levels of insects and pests inside the nuts may evade inspections. Groundnuts could become an important crop here and it is important not to bring in potentially invasive pest species that may feed on them.
We closely examined a bag of yellow groundnuts obtained from a food supplier located in Texas. Approximately 20% of the seeds were infested with unidentified insects. The infested seeds are shown in the photo below.
 Insect Damage in Bambara Groundnuts |
Updated Planting Instructions. Except in warm winter climates, the seeds should be started indoors and out planted when the weather warms. They require warm temperatures to germinate. Seeds started in cool or wet planting media are likely to not germinate and rot. Plant the seeds in moist rapidly draining media. We have had the best results using a mixture of 50% potting soil, 50% sand, which can result in germination rates near 100%. Do not soak the seeds before planting. This promotes rot and may result in 70 – 80% losses. The use of organic fungicides on the seeds has not improved germination rates and does not appear to be necessary when planting in artificial media.
Cuttings: This plant is not grown from cuttings.
Improved Cultivars
Many cultivars of this species have been developed. Refer to the BamNetwork (CF 2022) for additional information about these. Several color varieties are common: yellow, dark brown, black, red, blue, white and mottled.
Photoperiod control is required for good growth of groundnuts. Four classes of landraces have been identified for different photoperiod growing conditions. These are referenced on the BamNetwork website (CF 2022).
Pests and Diseases
Groundnuts are generally described as highly drought tolerant and relatively disease free. However, they have been reported to serve as major and minor hosts of many pests and diseases. These are listed and described in detail in the additional resources section of the CABI Invasive Species Compendium file for this species (CABI 2019).
Powdery Mildew. We have observed a significant percentage of leaves on our initial plantings of groundnuts at our Hawai`i facility infected with powdery mildew. On some plants the infected leaves remain on the plants while others wither and die. This disease is common on all of the Hawaiian islands and it affects many different many crops. Since the powdery mildew can grow at all but the lowest relative humidity, the disease can thrive in even the driest areas of Hawai‘i. Recent conditions of cool days and warm nights experienced in our area in the early summer of 2022 are known to favor infection and disease development. We are also in a very windy area and the spores are readily transmitted by wind. Refer to the publication by Nelson (2013) for additional information about this disease in Hawai`i.
We will investigate this to determine if there are apparent differences in susceptibility among the various varieties and test organic fungicides for mildew control. However, the very small scale of our initial local plantings may not yield definitive data.
 Powdery Mildew on Vigna subterranea |
Invasiveness Potential
Hawai‘i-Pacific Weed Risk Assessment (HPWRA) Program. Vigna subterranea has apparently not been assessed. It is not found on the Plant Pono website. We did not request assessment as it was previously introduced in Hawai`i.
Global Invasive Species Database Listing. This species was not found on the database (GISD 2022).
Plants and Seeds for Sale
Availability
Seeds. There are several suppliers of small packet amounts of groundnut seeds in the U.S. A brief survey conducted by us in June 2022 found most of these suppliers to be out of stock. This may reflect supply chain issues and increased seed demand stemming from recent news stories about groundnuts on CNN and other popular media.
We have limited supplies of seeds of the red, yellow and assorted color varieties of this species. Our seeds were obtained in 2022 from a supplier in Ghana. They were issued a phytosanitary certificate by the Inspection Division of the Ghana Ministry of Food and Agriculture before shipment and were re-inspected and passed by the U.S. Department of Agriculture before entry into Hawai`i. We also inspect all arriving seed shipments and the seeds are then treated by drying and freezing before sale to control insect pests that may have evaded detection.
Testing of samples of each seed lot was completed in August 2022 indicating germination rates of 75 – 100%.
Three varieties of these seeds are available for purchase from our online store. The specific germination rates for each seed are posted with the store listings.
Certified Nursery Stock. Organic (Certified Naturally Grown) seedlings of this species may be available by special order. Please contact us if you are interested.
 Bambara Groundnut Seedlings |
Reporting Results. Bambara groundnuts are an experimental crop and information on growing them in the U.S. is scant. We encourage our customers to report the results of plantings to us. We will make this information available for public use on this website.
Shipping Information
Groundnut seeds may be mailed to all locations in the United States and to most international destinations. Shipments from Hawai`i island to other islands in Hawai`i, and the U.S. mainland must be inspected by the Hawai`i Department of Agriculture before shipment. This service is provided to our customers at no charge. Seedlings may be shipped to all states except California.
Shipments of seeds to international destinations may require import permits and/or phytosanitary certificates issued by the U.S. Department of Agriculture. The fee charged for certificate issuance is $61.00. All shipments into countries in the European Union now require certificates. We do not offer seedlings for international shipment.
References
Recommended General References
BamNetwork is the online representation of the international research community on Bambara groundnut. The site aims to link researchers, students, farmers and end users together to facilitate the discussion and knowledge exchange on this crop (CF 2022). The website has an extensive listing of news items and publications.
PubMed listed over 300 scientific publications on groundnuts as of June 2022.
Review. See article by Udeh, Nyila, Kanu (2020).
Wikipedia Article –Vigna subterranea. Available: https://en.wikipedia.org/wiki/Vigna_subterranea
Review Articles and References Cited
Aliyu, S., Massawe, F., & Mayes, S. (2014). Beyond landraces: developing improved germplasm resources for underutilized species – a case for Bambara groundnut. Biotechnology & genetic engineering reviews, 30(1-2), 127–141. https://doi.org/10.1080/02648725.2014.992625
CABI (CAB International). 2019. Vigna subterranea (Bambara groundnut).In: Invasive Species Compendium. Wallingford, UK: CAB International. https://www.cabi.org/isc/datasheet/56585 [Accessed June 12, 2022].
Cairns R. 2022. This Singaporean startup has reinvented the instant noodle. CNN Business. https://www.cnn.com/2022/05/08/business/whatif-bamnut-sustainable-instant-noodles-climate-hnk-intl-spc/index.html [Accessed June 12, 2022].
Consortium of Pacific Herbaria (CPH). Herbarium Pacificum (Bishop Museum). Catalog # 56295. https://serv.biokic.asu.edu/pacific/portal/collections/individual/index.php?occid=581345&clid=0 [Accessed June 12, 2022].
Crops for the Future (CF). 2022. BamNetwork. http://bambaragroundnut.org/ [Accessed June 12 2022].
GISD (Global Invasive Species Database) 2022. https://www.iucn.org/search/Vigna%20subterranea Search performed on June 12, 2022.
Gregory, P. J., Mayes, S., Hui, C. H., Jahanshiri, E., Julkifle, A., Kuppusamy, G., Kuan, H. W., Lin, T. X., Massawe, F., Suhairi, T. A. S. T. M., & Azam-Ali, S. N. (2019). Crops For the Future (CFF): an overview of research efforts in the adoption of underutilised species. Planta, 250(3), 979–988. https://doi.org/10.1007/s00425-019-03179-2
Mabhaudhi T. 2013. Intercropping Taro and Bambara Groundnut. Sustainable Agriculture Reviews. 13:275-290. DOI: 10.1007/978-3-319-00915-5_9. https://link.springer.com/chapter/10.1007/978-3-319-00915-5_9 [Accessed June 12, 2022].
Mayes, S., Ho, W. K., Chai, H. H., Gao, X., Kundy, A. C., Mateva, K. I., Zahrulakmal, M., Hahiree, M. K. I. M., Kendabie, P., Licea, L. C. S., Massawe, F., Mabhaudhi, T., Modi, A. T., Berchie, J. N., Amoah, S., Faloye, B., Abberton, M., Olaniyi, O., & Azam-Ali, S. N. (2019). Bambara groundnut: an exemplar underutilised legume for resilience under climate change. Planta, 250(3), 803–820. https://doi.org/10.1007/s00425-019-03191-6
Nelson S. 2013. Powdery Mildew of Garden Vegetables in Hawai`i. Plant Disease. PD-98. Mānoa, Hawai`i: College of Tropical Agriculture and Human Resources. University of Hawai`i. https://www.ctahr.hawaii.edu/oc/freepubs/pdf/PD-98.pdf [Accessed September 04, 2022].
Panzeri, D., Guidi Nissim, W., Labra, M., & Grassi, F. (2022). Revisiting the Domestication Process of African Vigna Species (Fabaceae): Background, Perspectives and Challenges. Plants (Basel, Switzerland), 11(4), 532. https://doi.org/10.3390/plants11040532
Olanrewaju, O. S., Oyatomi, O., Babalola, O. O., & Abberton, M. (2022). Breeding Potentials of Bambara Groundnut for Food and Nutrition Security in the Face of Climate Change. Frontiers in plant science, 12, 798993. https://doi.org/10.3389/fpls.2021.798993
Tan, X. L., Azam-Ali, S., Goh, E. V., Mustafa, M., Chai, H. H., Ho, W. K., Mayes, S., Mabhaudhi, T., Azam-Ali, S., & Massawe, F. (2020). Bambara Groundnut: An Underutilized Leguminous Crop for Global Food Security and Nutrition. Frontiers in nutrition, 7, 601496. https://doi.org/10.3389/fnut.2020.601496
Udeh, E. L., Nyila, M. A., & Kanu, S. A. (2020). Nutraceutical and antimicrobial potentials of Bambara groundnut (Vigna subterranean): A review. Heliyon, 6(10), e05205. https://doi.org/10.1016/j.heliyon.2020.e05205
Utopian Seed Project (USP). 2022. Bambara Groundnut (Vigna subterranea). https://theutopianseedproject.org/project/bambara-groundnut/ [Accessed June 12, 2022].
Page last updated March 26, 2023.