Herb
Epazote
Dysphania ambrosioides · Amaranthaceae
Also called: Wormseed, Mexican Tea, Jesuit's Tea, Paico
Epazote (Dysphania ambrosioides) is a low-water herb well suited to Tucson and the low desert. It thrives in full sun, with a fast growth rate. Expect greenish (inconspicuous) blooms summer into fall.
Epazote at a glance
- Water use
- Low (established)
- Sun
- Full sun; thrives in Tucson's heat and full exposure once established.
- Mature size
- 2–4 ft tall and 1–2 ft wide; can reach 3–4 ft in good conditions.
- Growth rate
- Fast
- Bloom
- Greenish (inconspicuous), Summer into fall; tiny inconspicuous greenish flowers followed by abundant seed. Best to remove before seed sets.
- Cold hardiness
- Warm-season; frost-tender top growth dies back with freezes but it behaves as a short-lived perennial/self-seeding annual in USDA 9–12 and reliably returns from seed each spring.
- Soil
- Tolerates poor, dry, alkaline soils including native desert soil and disturbed ground; prefers well-drained soil. Very adaptable.
- Native range
- Tropical Mexico, Central and South America; long naturalized across the southwestern U.S. (historically grown at Mission San Xavier del Bac near Tucson).
- Best used as
- Traditional Mexican culinary herb (essential in black bean dishes—reduces gas, flavors quesadillas, soups), Medicinal/folk use, Pollinator and pest-deterrent companion plant
- Wildlife
- Aromatic foliage tends to deter some insects; minor pollinator value.
- Toxicity
- The leaf is a culinary herb in small amounts, but the plant contains ascaridole (concentrated in the essential oil and seeds), which is toxic in large quantities and the concentrated oil is dangerous—keep away from pets and children and avoid ingesting large amounts. Use sparingly as a seasoning only.
How to grow Epazote in Tucson & the low desert
Watering
A warm-season herb—plant from seed or transplant after frost (spring through the monsoon, March–August). Drought-resistant once established; water deeply about once a week in summer and let the soil dry between irrigations. Overwatering produces lush but weak, less flavorful growth.
Fertilizer & nutrients
Very light feeder—rarely needs fertilizer. Amend with a little compost at planting; avoid heavy nitrogen, which dilutes the pungent flavor and encourages floppy growth.
Pruning & care
Pinch tips to keep plants compact and harvest leaves continuously. Remove flower/seed heads before they mature to prevent prolific self-seeding (it can become weedy).
Notes
Self-seeds aggressively in the low desert—deadhead to control spread. Strong, pungent flavor; a little goes a long way. Genus reclassified from Chenopodium ambrosioides to Dysphania ambrosioides. Reliable monsoon-season performer in Tucson.
Sources: University of Arizona Cooperative Extension; Savor the Southwest (Tucson) garden blog; Elgin Nursery & Tree Farm (AZ) plant notes; Wikipedia: Dysphania ambrosioides (ascaridole toxicity)