Mexican Tea (Chenopodium ambrosioides)

Annual/Perennial
Common Name Latin Name Plant Family
Mexican Tea
Chenopodium ambrosioides
Chenopodiaceae

The plant is used as a fumigant against mosquitoes and is also added to fertilizers to inhibit insect larvae[238].

Gold/green dyes can be obtained from the whole plant[168].

  • Medicinal Use

    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].

  • Edible Use

    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].

  • Cautionary Notes

    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].

Cultivation & Habitat

Seed – whilst it can be sown in situ in mid to late spring, we have had better results by sowing the seed in a cold frame in early spring. Put a few seeds in each pot and thin to the best plant if necessary. Germination rates are usually very good and the seedlings should appear within a few days of sowing the seed. Plant out in late spring, after the last expected frosts.
An easily grown plant, succeeding in most soils but disliking shade[1, 200]. It prefers a moderately fertile soil[200]. Tolerates a pH in the range 5.2 to 8.3. Plants are annuals or short-lived perennials[238]. They are not very hardy when grown outdoors in Britain and so are best grown as an annual[238]. Plants have often self-sown freely in our Cornish trial grounds, but the seed often germinates in the autumn and then does not manage to survive the winter[238]. This species is sometimes grown as a medicinal and culinary plant, especially in its native Mexico. The sub-species C. ambrosioides anthelminticum is more active medicinally and is the form most often cultivated for its vermicidal activity[238]. The bruised leaves emit an unpleasant foetid odour[245].
Tropical America. Naturalized in S. Europe[50].

Become ungovernable, break the chains of the matrix; grow and forage your own food and medicine.

*None of the information on this website qualifies as professional medical advice. Take only what resonates with your heart and use your own personal responsibility for what’s best for you. For more information [brackets] [000], see bibliography.