Sneezewort, or Achillea ptarmica, is a perennial plant in the genus Achillea in the Asteraceae family, also known as the aster family. It is an erect plant with white to off-white flowers and simple to highly-branched hairy stems. This plant’s flat-topped inflorescence, a cluster of flowers that grow on a stem, is composed of small white petals surrounding a green disc in the middle. It is also known by the common names sneezeweed and brideflower. This plant can grow up to 3 feet (about 0.9 m) tall.
The flowers of the sneezewort plant bloom in late June to mid-September. These flowers can self-pollinate, as they bear both male and female reproductive organs, although bees and flies also help in pollination. The plant has narrow green leaves that measure up to 2 inches (about 5 cm) long, are smooth on the upper surface, and have saw-toothed edges. Its flowers produce one-seeded fruits that are roughly 0.04 to 0.08 inches (1 to 2 mm) long.
Native to Europe, the sneezewort became naturalized in North America after escaping cultivation. The plant’s spreading root system has helped in this process, aside from its fast growth rate and hardiness. These characteristics are also reasons why the plant has the potential to be invasive. The plant’s usual habitats are roadsides, open fields, and pastures. As this plant is poisonous to cattle, horses, and sheep, these animals should not be allowed to graze in pastures where the plant is growing.
Sneezewort can grow best in all soil types as long as they are moist and well drained. It can even grow in dry and nutritionally poor soil, although it should be planted in a sunny location since it grows poorly in the shade. Tolerant to maritime exposure as well as periods of drought, it can be susceptible to powdery mildew, a fungal disease that affects many plants. Propagation of sneezewort is through seed or plant division. Any of these propagation methods can be utilized in the spring or autumn, when they will have enough time to germinate, root and be ready to plant outdoors the next summer.
The primary reason for cultivation of sneezewort is for ornamental and garden use. Sneezewort flowers are sometimes used in flower arrangements, either as fresh or dried cut flowers. Its leaves also are edible and can be eaten raw or cooked, usually as an ingredient in salads. Sneezewort leaves can also be dried and ground into powder to make sneezing powder. The leaves also can be used as an insect repellent and for toothache relief.