Mexican Tea. Epazote.

Chenopodium ambrosioides

Physical Characteristics

Chenopodium ambrosioides is a ANNUAL/PERENNIAL growing to 1 m (3ft 3in) by 0.7 m (2ft 4in). See above for USDA hardiness. It is hardy to UK zone 7 and is frost tender. It is in flower from July to October, and the seeds ripen from August to October. The species is hermaphrodite (has both male and female organs) and is pollinated by Wind. Suitable for: light (sandy), medium (loamy) and heavy (clay) soils. Suitable pH: mildly acid, neutral and basic (mildly alkaline) soils and can grow in very alkaline soils. It cannot grow in the shade. It prefers moist soil.

Distribution

Tropical America. Naturalized in S. Europe[50].

Habitats

Cultivated Beds;

Edible Uses

Edible Parts: Leaves Seed Edible Uses: Tea Only a very small amount of leaf may be used safely as a culinary seasoning. Strong, resinous flavor; unmistakable aroma; meaningful toxicity. Seeds and large quantities of leaves must be avoided. Best understood as a cultural herb, not a wild edible plant. Leaves - cooked[2]. The tender leaves are sometimes used as a potherb[183]. Used as a condiment in soups etc[46, 61, 105], they are said to reduce flatulence if eaten with beans[183]. The leaves have a rank taste due to the presence of resinous dots and sticky hairs[85]. The raw leaves should only be eaten in small quantities, see the notes above on toxicity. Seed - cooked[105, 161]. The seed is small and fiddly, it should be soaked in water overnight and thoroughly rinsed before it is used in order to remove any saponins. An infusion of the leaves is a tea substitute[183]. Edible Uses & Rating: Only the leaves, used sparingly as a culinary herb, can be considered edible, and even then, only with caution. All other parts—particularly the seeds—should be avoided as food due to their high ascaridole content. As an herb, epazote brings a distinctive flavor profile that has been central to traditional Mexican cooking for centuries, but as a wild edible plant, it rates extremely low because it provides no safe bulk nutrition, is chemically unstable, and carries documented toxicity risks. In a culinary context, however, it is valued as a seasoning rather than a consumed vegetable [2-3]. Taste, Processing & Kitchen Notes: Epazote’s flavor is intensely herbaceous, resinous, and medicinal. Fresh leaves can evoke associations with turpentine, varnish, creosote, citrus, savory, menthol, oregano, or even skunk musk—descriptions that reflect its complex chemistry more than its culinary appeal. When used in very small quantities, the herb adds depth to bean dishes, helping neutralize gas-producing compounds and enhancing digestibility [2-3]. Dried epazote develops a milder, hay-like aroma reminiscent of an herbarium, lacking the sharper resinous notes of the fresh plant. The transformation from fresh to dried is dramatic: drying softens many of the aggressive tones but also reduces culinary power. In traditional cooking, fresh leaves are preferred, added in the last minutes of cooking to preserve volatile aromatics [2-3]. Epazote should never be used in bulk. A few leaves suffice for a pot of beans; more than that introduces risk of nausea or neurological symptoms. Seeds must never be used as food. Seasonality (Phenology): Epazote emerges in spring and grows vigorously through the heat of summer, thriving in warm soils and full sun. Flowering usually begins mid- to late summer, with seeds maturing in early autumn. Because the plant reseeds heavily, it often appears year after year in gardens or disturbed sites. Safety & Cautions (Food Use): This species requires significant caution. Epazote contains ascaridole, a potent neurotoxin and gastrointestinal irritant. Historically used to expel intestinal worms, ascaridole is toxic at moderate doses and can cause nausea, headache, dizziness, disorientation, heartbeat irregularities, convulsions, or coma. Toxicity is greatest in the seeds and essential oil, but leaves also contain substantial amounts. Heating reduces but does not eliminate ascaridole completely. Use only in very small culinary amounts. Avoid during pregnancy, breastfeeding, or in individuals with liver, kidney, or neurological disorders. Seeds should never be eaten. Harvest & Processing Workflow: Harvest fresh leaves sparingly, selecting young shoots with the mildest flavor. Rinse thoroughly. For cooking, add leaves late in the process to retain their aromatic properties. For drying, hang small bundles in shade with good airflow; store dried leaves airtight. Do not harvest seeds. Any plant parts intended for culinary use should be handled cautiously and measured carefully. Look-Alikes & Confusion Risks: Other Dysphania and Chenopodium species resemble epazote but lack its penetrating odor. Oakleaf goosefoot (Dysphania botrys) and fetid goosefoot (Dysphania graveolens) also emit strong scents but differ in leaf shape and resin glands. Mild goosefoots such as lambsquarter can be distinguished by their mealy leaf coating and mild aroma. For safety, rely on smell: epazote’s volatile odor is unmistakable. Traditional / Indigenous Use Summary: Across Mesoamerica, epazote has been used for centuries as a culinary herb and medicinal vermifuge. Indigenous peoples valued it as a parasite remedy, a digestive aid for bean dishes, and a seasoning for classic foods such as black beans, tamales, and moles. In the United States, it holds minimal ethnobotanical presence among Southwest tribes, largely because it is not strongly native there. Historical medicinal uses involved extremely careful dosing due to the plant’s toxicity.

Medicinal Uses

Analgesic Antiasthmatic Antifungal Carminative Dysentery Stomachic Vermifuge Mexican tea is a Central American herb that has been used for centuries to expel parasitic worms from the body[254]. The whole plant is analgesic, antiasthmatic, carminative, stomachic and vermifuge[1, 4, 21, 57, 145, 147, 171]. An infusion can be used as a digestive remedy, being taken to settle a wide range of problems such colic and stomach pains[254]. Externally, it has been used as a wash for haemorrhoids, as a poultice to detoxify snake bites and other poisons and is thought to have wound-healing properties[254]. Use with caution and preferably under the supervision of a qualified practitioner[21, 238]. This remedy should not be prescribed for pregnant women[238]. See also the notes above on toxicity. Until fairly recently, this was one of the most commonly used vermifuges, though it has now been largely replaced by synthetic drugs[222]. The seed, or an essential oil expressed from the seed, was used[213]. It is very effective against most parasites, including the amoeba that causes dysentery, but is less effective against tapeworm[213, 238]. Fasting should not precede its use and there have occasionally been cases of poisoning caused by this treatment[213]. The oil is used externally to treat athlete's foot and insect bites[238]. One report says that it is an essential oil that is utilised[240]. This is obtained from the seed or the flowering stems, it is at its highest concentration in the flowering stems before seed is set, these contain around 0.7% essential oil of which almost 50% is the active vermifuge ascaridol[240]. The essential oil is of similar quality from plants cultivated in warm climates and those in cool climates[240]. The leaves are added in small quantities as a flavouring for various cooked bean dishes because their carminative activity can reduce flatulence[222].

Known Hazards

The essential oil in the seed and flowering plant is highly toxic. In excess it can cause dizziness, vomiting, convulsions and even death[222, 238]. The plant can also cause dermatitis or other allergic reactions[222]. The leaves and seeds of all members of this genus are more or less edible. However, many of the species in this genus contain saponins, though usually in quantities too small to do any harm. Although toxic, saponins are poorly absorbed by the body and most pass straight through without any problem. They are also broken down to a large extent in the cooking process. Saponins are found in many foods, such as some beans. Saponins are much more toxic to some creatures, such as fish, and hunting tribes have traditionally put large quantities of them in streams, lakes etc in order to stupefy or kill the fish[K]. The plants also contain some oxalic acid, which in large quantities can lock up some of the nutrients in the food. However, even considering this, they are very nutritious vegetables in reasonable quantities. Cooking the plant will reduce its content of oxalic acid. People with a tendency to rheumatism, arthritis, gout, kidney stones or hyperacidity should take especial caution if including this plant in their diet since it can aggravate their condition[238].