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Quassia amara - L.

Common Name Bitterwood, Amargo Bark
Family Simaroubaceae
USDA hardiness 10-12
Known Hazards None known
Habitats An understorey plant in rainforests and humid sites[307 ].
Range Northern S. America - Guiana, northern Brazil and Venezuela.
Edibility Rating    (2 of 5)
Other Uses    (2 of 5)
Weed Potential No
Medicinal Rating    (4 of 5)
Care (info)
Tender Moist Soil Semi-shade Full sun
Quassia amara Bitterwood, Amargo Bark
Quassia amara Bitterwood, Amargo Bark


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Quassia amara or commonly known as Bitterwood or Amargo is a small evergreen shrub growing only about 3 m in height. It bears a small drupe, red flowers, and compound, alternate leaves. Though it is mainly cultivated throughout Northern South America as an ornamental tree, it is also valued for its edible and medicinal uses. In particular, bark extracts are used as flavoring in drinks. Medicinally, all plant parts are useful. It restores appetite, stimulates digestion, and treats various conditions such as fever, measles, malaria, diarrhea, dysentery, urinary tract disease, liver cirrhosis, alcoholism, diabetes, albuminuria, ulcers, smallpox, etc. Propagation can be through seeds and cuttings.

Physical Characteristics

 icon of manicon of shrub
Quassia amara is an evergreen Shrub growing to 5 m (16ft) by 5 m (16ft) at a slow rate.
It is hardy to zone (UK) 10 and is frost tender. The flowers are pollinated by Hummingbirds.
Suitable for: medium (loamy) and heavy (clay) soils. Suitable pH: acid, neutral and basic (alkaline) soils. It can grow in semi-shade (light woodland) or no shade. It prefers moist soil.

UK Hardiness Map US Hardiness Map


Quassia alatifolia Stokes Quassia officinalis Rich.


Edible Uses

Edible Parts: Inner bark
Edible Uses:

The bitter principle found in the bark and wood is used as the basis of Angostura Bitters, which is used as a flavouring in gin-based drinks[307 ]. It is also used as a substitute for hops when brewing beer[301 ].


Medicinal Uses

Plants For A Future can not take any responsibility for any adverse effects from the use of plants. Always seek advice from a professional before using a plant medicinally.

All parts of the plant contain a bitter principle called quassimarin[307 ]. This has a range of medical properties including antileukaemic, antitumor, astringent, digestive, febrifuge, laxative, tonic and vermifuge[307 ]. Quassimarin has been shown to stimulate the secretion of gastric juices, increase the appetite and aid digestion[307 ]. It has been used successfully in the treatment of anorexia nervosa and is also used in the treatment of malaria and fevers[307 , 348 ]. All parts of the plant can be used on their own or in combination to restore the appetite, stimulate digestion and combat fevers, including malaria[348 ]. A tea made from the infused leaves is used to bathe the skin of measles patients[307 ]. It is also used as a mouthwash after tooth extractions[307 ]. A decoction of the bark is used as a blood purifier and to treat malaria, diarrhoea and dysentery[348 ]. A decoction of the inner bark is used to treat colds[348 The stem and bark are used in remedies for treating diseases of the spleen, liver (cirrhosis), and urinary tract[348 ]. The bark is used for treating the weak eyes of alcoholics and, macerated in rum, as a vermifuge[348 ]. Combined with the macerated stem of Tinospora crispa in rum, cognac or absinthe, it is used to make a beverage for treating diabetes and albuminuria[348 ]. A decoction of the wood is used in lotions as a wash for persistent venereal ulcers[348 ]. A decoction of the bark and leaves is used as a wash to rid the skin of external parasites such as agouti lice and as a treatment for measles and smallpox[348 ]. Stem-bark contains the insecticidal compounds neoquassine and quassine[348 ]. Sap shows activity against cells derived from carcinoma of human nasopharynx[348 ]. Plant extracts contain the antileukemic compounds quassimarin and similikalactone[348 ].


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Other Uses

Humid shade garden. large container. Accent. Botanic collection. Conservatory. Other Uses: All parts of the plant, but especially the bark and young stems, can be used as an insecticide[307 ]. Crushed leaves, placed on body, reputedly act as a mosquito repellent[348 ].

Special Uses


Cultivation details

A plant for the humid tropics[200 ]. Prefers a fertile, moist but well-drained soil in a partially shaded position[302 , 307 ]. Bloom Color: Scarlet (Dark Red). Spacing: over 40 ft. (12 m).


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Plants For A Future have a number of books available in paperback and digital form. Book titles include Edible Plants, Edible Perennials, Edible Trees, and Woodland Gardening. Our new book to be released soon is Edible Shrubs.

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Seed - Cuttings of half-ripe wood

Other Names

If available other names are mentioned here

Hombre grande, Kwasibita, Asoemaripa, amargo, bitterholz, bitterholzbaum, bitterquassia, bitterwood, bois amer, crucete, cuasia, cuasia amarga, hombre grande, jamaica quassia, kvassia, kwasi beta|weradi sinchona, pau-amarelo, pau-amargo, pau-quássia, quassia, quassia amara, quassia de surinam, quassia surinam, quassia-wood, quassiae lignum, quassiaholzbaum, quassie, quina, quinarana, quinine de cayenne, quinine du pays, quássia-de-caiena, su, surinam quassia, wéwe gífi.

Found In

Countries where the plant has been found are listed here if the information is available

Colombia; Mexico; Guatemala; Honduras; Nicaragua; Costa Rica; Panama; French Guiana; Guyana; Suriname; Venezuela, Bolivarian Republic of; Brazil; Guadeloupe; Martinique; Saint Vincent and the Grenadines, Belize, Brazil, Central America, Colombia, Costa Rica, Dominican Republic, El Salvador, Guadeloupe, Guatemala, Guiana, Guyana, Haiti, Honduras, Mexico, Nicaragua, North America, Panama, Peru, Puerto Rico, SE Asia, Singapore, South America, Suriname, Venezuela,

Weed Potential

Right plant wrong place. We are currently updating this section. Please note that a plant may be invasive in one area but may not in your area so it’s worth checking.

Conservation Status

IUCN Red List of Threatened Plants Status : This taxon has not yet been assessed

Related Plants
Latin NameCommon NameHabitHeightHardinessGrowthSoilShadeMoistureEdibleMedicinalOther
Picrasma excelsaJamaican QuassiaTree20.0 10-12 MLMNM244

Growth: S = slow M = medium F = fast. Soil: L = light (sandy) M = medium H = heavy (clay). pH: A = acid N = neutral B = basic (alkaline). Shade: F = full shade S = semi-shade N = no shade. Moisture: D = dry M = Moist We = wet Wa = water.


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Botanical References

Links / References

For a list of references used on this page please go here
A special thanks to Ken Fern for some of the information used on this page.

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