The plant, which is often referred to under his old botanical name, Chenopodium ambrosioides, is a tall, narrow herb with large, soft, oval, notched leaves that grow up to 4 inches long and 1 1/2 inches across. The leaf color ranges from green to yellowish-green or reddish-green. The stems are reddish, cream-colored, or green. The strong smell of the plant comes from tiny glands on the stems and leaves that secrete a highly scented oil. The plant grows small, yellow-greenish and inconspicuous flowers from mid-summer to fall. Planting time is in the late spring after all danger of frost has passed. Only the leaves of epazote are edible. The other plant parts, especially the seeds, are toxic to humans, and toxic to pets. Epazote has one other drawback: its leaves contain the compound ascaridole, which can inhibit the growth of other plants nearby. If you have young plants that are not yet fully established, or tender seedlings, it is better not to plant epazote next to it. However, epazote can also be a beneficial companion plant because its flowers attract predatory wasps and flies. The strong odor of epazote, which can be smelled from a few feet away, can help deter pests from other plants that are prone to infestations.
Epazote Care
Light
While epazote is undemanding in most of its growing conditions, sufficient light it a must. It needs full sun to thrive.
Soil
The herb can grow in many soil types and in a wide pH range from acidic to alkaline (5.2 to 8.3). Avoid planting it in a location with poor drainage as it does not like wet feet. Acidic soil tends to reinforce the purpling of the stems and leaf veins.
Water
Until the plant is established, epazote needs regular watering to keep it evenly moist. Afterwards, it is drought-tolerant.
Temperature and Humidity
Epazote can tolerate a light frost but won’t survive a harsh winter. It is a tropical plant that is adapted to moderately humid conditions as well are semi-arid climate.
Fertilizer
The plant grows in soils of all fertility levels, from moderately fertile soil to poor soils and fertilization is usually not necessary unless the plant becomes, chlorotic, which is more likely with container-grown plants. Epazote is said to even grow in pavement cracks.
Types of Epazote
The only known variety of epazote is ‘Oaxacan Red’, a red-leafed variety.
Harvesting Epazote
You can start harvesting the leaves any time after the plant is established and has developed lush foliage. Pick the largest leaves but harvest them when they are still young because the flavor becomes stronger with age and might become overpowering. The best time to pick is in the morning after the dew has dried.
How to Grow Epazote in Pots
The herb is not unlike mint—you often get more than you wish for, and the plant can become invasive. And just like mint, a good way of controlling the spread of the plant is by growing it in a container. If you live in USDA zones 8 to 10 where epazote is a perennial, you can even bury the container in the ground. A 1-gallon pot is usually a good size for one epazote plant, which usually provides enough leaves for home cooking. Terra cotta is the preferable material as it lets excess moisture can evaporate (epazote does not like wet feet). It is also less likely to topple over, as epazote is a tall, rather narrow plant.
Pruning
Epazote readily self-seeds and pops up in unwanted places but this can be prevented by simply removing the flowers before they can turn into seeds. It can also become weedy. Regular pruning takes care of both issues. To encourage a bushy, compact growth, cut out the center stalk with a sharp knife or pruners and pinch off the stem tips. Pinch off the flowers as soon as they emerge, which encourages more leaf growth, and also prevents the plant from reseeding itself.
Propagating Epazote
Because epazote is so easily grown from seed, rather than propagating it vegetatively from cuttings, growing it from seed is the preferred propagation method.
How to Grow Epazote from Seed
You can grow epazote from seeds either by direct seeding after all danger of frost has passed, or, to get a head start on the growing season, by starting the seeds indoors between late March and early May. The timing depends on your last frost date, you don’t want the seedlings ready for transplanting outdoors too early.
Potting and Repotting Epazote
When grown as an annual, epazote won’t need repotting during its single growing season. When grown as a perennial, there is usually no point in repotting it in a larger pot as the idea of container growing is to keep the plant contained. However, if the epazote starts to outgrow its container, you can remove it from the pot in the spring, divide it so it fits the pot (and discard the extra section, give it away, or repot it in a second pot), then replant it in the same container with fresh potting mix.
Overwintering
In warm climates, epazote does not need any winter protection. Below USDA zone 8, it is grown as an annual whose life cycle ends with the first strong frost in the fall. Because it is difficult to give epazote the same amount of sunlight as outdoors, overwintering it indoors is not a recommended option.
Common Pests and Plant Diseases
The strong odor of epazote deters most pests but it can be attacked by aphids, flea beetles, ground beetles, cabbage loopers, root nematodes, and slugs. It is also prone to get downy mildew.