Dysphania ambrosioides aka Epazote

Dysphania ambrosioides has three common names: epazote, Mexican tea, and wormseed. It belongs to the Amaranthaceae family. Its old name is Chenopodium ambrosioides. Kew places its native range from the eastern and southeastern United States to Colombia. This range includes the Caribbean. It also grows beyond this range, including in Europe. This herb lives for one year or a few years. It grows fast and forms many uneven side branches. Plants reach about 2–5 feet [0.6–1.5 metres] tall.

The upright stems are round, smooth, and free of hairs. Their clear veins show green, dull red, or cream tones. Small glands on stems and leaves give off strong-smelling oil. The scent can seem musky and unpleasant. Each leaf has one blade, and leaves grow in turn along the stems. They range from green to yellow-green. Their bases have a wedge shape. Leaves are about 3–4 inches long and 1.5 inches wide. A single plant may have several kinds of leaf edges. Some are smooth, while others have teeth or lobes.

Small green flowers bloom from midsummer through fall. They form tight groups on spikes at the stem tips. Small leaf-like bracts sit among the flowers. Each flower measures about a quarter-inch across. The plant can use its own pollen to set seed. Wind also carries its pollen. It makes many seeds, and fallen seeds sprout with ease. Its small oval fruits are achenes, a type of dry fruit. Their sepals stay in place and curve inward. The seeds have an egg shape and turn almost black. Songbirds, gamebirds, and mice eat them.

Grow epazote in full sun with soil that drains well. It prefers moist soil with a fair supply of nutrients. It accepts clay, loam, and sand, and tolerates some dry periods. It also grows on sandy or rocky disturbed ground. Plants cope with heat but are not very hardy outdoors in Britain. There, growing it as an annual suits its short life. PFAF lists USDA zones 6–11 and soil pH 5.2–8.3. Its main garden problem is that it self-seeds and becomes a weed. It grows in fields, roadside ground, and waste sites.

People use small amounts of leaf to season Mexican dishes. These include bean dishes, soups, and stews. Its strong taste makes it a seasoning, not a bulk food. Past uses include treating worms, controlling insects, and making plant dyes. The dose used against worms can also poison people. Avoid seeds and large amounts of leaves as food. The oil in a strong form can cause vomiting. It can also cause convulsions and even death. ASPCA lists it as toxic to dogs, cats, and horses. These animals may vomit or have diarrhea if they swallow the oil. Sources disagree on whether skin contact can cause dermatitis, a skin rash.