Nasturtium

Tropaeolum majus

Other names: Garden nasturtium, Indian cress, Tropaeoli majoris herba

Edible plant

European

Photo credit: George Chernilevsky / Wikimedia Commons

Safety information

Toxicity: Low at culinary/traditional doses; isothiocyanates are mucosa-irritant — high doses can cause GI/mucosal and (rarely) stomach irritation.

Contraindications: Gastric/duodenal ulcers and kidney inflammation (isothiocyanate irritation); infants/young children; pregnancy/lactation (insufficient data for medicinal doses).

Interactions: None firmly established; theoretical additive mucosal irritation with other isothiocyanate/mustard-oil herbs (horseradish, mustard) and NSAIDs.

Pregnancy & breastfeeding: Insufficient data for medicinal doses — avoid.

Evidence level

Clinical

Supported by clinical trials in humans.

Preparations

edible-raw · leaf

Part used: leaf

Traditional use: peppery salad green(Folk and historical sources have not been validated by clinical research.)

Proposed mechanism: glucotropaeolin → benzyl isothiocyanate (mustard oil)

Evidence:Folk

infusion · aerial parts

Part used: aerial parts

Traditional use: urinary antiseptic / respiratory infection (with horseradish)

Proposed mechanism: benzyl isothiocyanate excreted in urine — antimicrobial

Dosage note (descriptive only): GI/ulcer/kidney caution at medicinal doses

Evidence:Clinical

General preparation guide →

Associated conditions

minor urinary-tract infections respiratory infections urinary antiseptic

Edibility

Edible parts: leaves and flowers raw (peppery, cress-like) in salads; unripe seeds pickled as a caper substitute

Toxic lookalike warning

Cultivated nasturtium is distinctive (round peltate leaves, spurred flowers) and rarely confused; when foraging, do not confuse ornamental garden nasturtium with unrelated 'cresses'

Nutritional notes

Leaves/flowers provide vitamin C and carotenoids; glucosinolate (mustard-oil) phytochemicals; a functional peppery salad green

Healing traditions

European

Sources (3)

A combination of Tropaeolum majus herb and Armoracia rusticana root for the treatment of acute bronchitis (ScienceDirect, 2023)
Nasturtium (Tropaeolum majus) — Herbal Reality (EN)
The Glucosinolate–Myrosinase System in Nasturtium (Tropaeolum majus L.) (J. Agric. Food Chem., 2008)

All sources →