• This is the flower of Apios americana, or American groundnut, a native legume species.

  • A quick look at the origins of the plants explored on this page.

This page is a collaboration between the UVM Center for Sustainable Agriculture and Eric Bishop von Wettberg of the Plant & Soil Science Department. We are glad to promote the uses of tuberous legumes as traditional and new crops that present opportunities for vegetable farm diversification and economic viability, aid in soil remediation, and share variety within the local food movement and market.

The initial content and images on this page were developed by CALS student Mackenzie Laverick '22, and we look forward to expanding this content over time.

Legumes, in the family Fabaceae, are known for their stipulate compound leaves, bean or pea style fruit, and abilities to fix nitrogen. Tuberous legumes are unique in their elongated or enlarged roots that are often edible, high in protein and starches, and have the potential to act as natural bio-drills to break up compacted soils. The tubers and many other parts of the plant like beans/seeds, flowers, and shoots are edible. These legumes hail from countries across the world with varied cultural histories, many with ancient roots in food and medicine, giving them a unique ethnobotanical background.

Over time, UVM PSS students will study 10 legumes and share their findings here:

  • Apios americana (groundnut, hopniss),
  • Glycine tomentella (wild soybean),
  • Lathyrus linifolius (everlasting pea),
  • Melilotus alba (white sweet clover),
  • Pachyrhizus tuberosus (Jicama),
  • Phaseolus coccineus (Scarlet runner bean),
  • Psophocarpus tetragonolobus (winged bean), 
  • Sphenostylis stenocarpa (African yam bean),
  • Vigna lanceolata (Bush carrot), and
  • Vigna vexilata (Zombi pea).

African Yam Bean

image description: a vining plant with deep black-red flowers climbing a narrow stake

Sphenostylis stenocarpa or African yam bean is a Sub-Saharan African legume with an edible tuber and beautiful deep violet flowers. The flowers are ant and wasp pollinated and the seed pods from this plant explode with heat!

American Groundnut

image description: a maroon and purple frilly, showy flower with large green leaves inside a greenhouse.

Apios americana or American groundnut, this legume is native to Vermont and the tuber, seeds, shoots, and flowers are all edible.

Bush Carrot

image description: a deep maroon flower on a green plant in the field.  This is a cowpea.

Vigna lanceolata or Bush carrot, is an endemic Australian legume with an edible tuber full of protein, carbohydrates, vitamins, and minerals.  Here's a video in the Dalabon language  (with English subtitles) showing how it's found and dug up.

Everlasting Pea

image description: a hand holds the stem of a plant with several narrow leaves

Lathyrus linifolius or everlasting pea is a European legume whose tuber is often roasted and consumed as an appetite suppressant or used as a flavoring in drinks to add a licorice-like taste.


image description: close up a broad-leafed green vining plant climbing up a pole or trellis

Pachyrizus tuberosus or Jicama is a mesoamerican legume with a giant tuber that is cultivated for commercial use.

White Sweet Clover

image description: green plants with round leaves growing in a mulched field

Melilotus alba or white sweet clover is a native Eurasian legume whose leaves are used medicinally as a tea. This plant is a great forage crop for livestock and has great potential for soil remediation as an effective nitrogen fixer.

Wild Soybean

image description: small purple flowers on a low-growing green plant

Glycine tomentella or wild soybean is a native Asian plant closely related to Glycine max (the commercial soybean) with edible tubers and seeds. It is also used medicinally as the root can be ground into an herbal tea.

Winged Bean

image description: a vining plant with beans with frilly edges climbing a pole

Winged bean’s pod has a crazy tetrahedral shape which is where the species gets its name “tetragonolobus”. The young pods can be cooked just like green beans and taste very similar. 

Zombi Pea

image description: rich green leaves and delicate flowers growing low to the ground

Vigna vexilata or zombi pea, is an African and Indonesian legume with an edible tuber and seeds. This plant has a wide distribution and grows surprisingly well in the desert.


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