Feverwort is a common name often used interchangeably with feverfew (Tanacetum parthenium), a well-known plant in the daisy family.
Identifying Feverwort
Tanacetum parthenium, commonly known as feverfew, is an herbaceous perennial in the Asteraceae family, which includes daisies and sunflowers. It typically forms bushy, rounded clumps, growing between 1 to 3 feet tall and spreading about 1 to 2 feet wide. The plant features delicate, fern-like, pinnately lobed leaves that are light yellowish-green and release a strong, pungent, citrusy fragrance when crushed.
Its most recognizable feature is its abundance of small, daisy-like flowers that bloom from late spring through late summer. These flowerheads, roughly 0.5 to 1 inch in diameter, consist of numerous white ray florets surrounding a central disc of yellow tubular florets. Native to Eurasia, particularly the Balkans, Anatolia, and the Caucasus, feverfew has spread globally, often found in cottage gardens, naturalized areas, and along roadsides. It can sometimes be mistaken for German chamomile or ox-eye daisy due to similar flower appearances, but feverfew’s flatter flower base helps distinguish it.
Traditional and Contemporary Applications
Feverfew has a long history of use in traditional medicine, particularly in Europe, dating back over 2,000 years. Its name, derived from the Latin word “febrifugia,” meaning “fever reducer,” reflects its historical application in treating fevers and other inflammatory conditions. Beyond fevers, it was widely employed to address headaches, including migraines, as well as joint pain associated with conditions like rheumatoid arthritis.
Traditional preparations often involved consuming the leaves or making infusions, such as teas, to harness its properties. The plant contains active compounds, primarily parthenolide, found in its leaves. Research suggests that parthenolide may contribute to the plant’s anti-inflammatory effects by inhibiting substances in the body that promote inflammation.
Contemporary interest in feverfew continues, with research exploring its potential for preventing and reducing the severity and frequency of migraine headaches. Studies indicate that compounds in feverfew might help by inhibiting serotonin receptors, preventing blood platelets from releasing inflammatory molecules, and affecting blood vessel dilation. While traditionally used for various ailments, the scientific community emphasizes the need for more clinical evidence to support many of its pharmacological uses.
Important Safety Considerations
Despite its history of use, feverfew has potential side effects and contraindications. Some individuals may experience digestive upset, including stomachaches, heartburn, diarrhea, constipation, or bloating when taking dried feverfew leaf or extract. Chewing fresh feverfew leaves can cause mouth sores, swelling of the mouth, and a temporary loss of taste.
Allergic reactions can occur, especially in individuals sensitive to plants in the Asteraceae family, which includes ragweed, chrysanthemums, and marigolds. Additionally, feverfew may slow blood clotting, increasing the risk of bleeding. Therefore, it should be discontinued at least two weeks before any scheduled surgery. Feverfew is considered unsafe during pregnancy due to concerns it might induce early contractions or miscarriage. Safety information during breastfeeding is insufficient, so avoid use. People with bleeding disorders or those taking blood-thinning medications should use feverfew cautiously due to its potential to interact with these medicines. Always consult a healthcare professional before incorporating feverfew into your regimen, especially if you have existing health conditions or are taking other medications.
Growing and Harvesting Feverwort
Cultivating Tanacetum parthenium is straightforward, as it is a low-maintenance plant. Feverfew thrives in full sun, ideally receiving at least six to eight hours of direct sunlight daily, though it can tolerate partial shade. It prefers well-drained, moist soil with a neutral pH, ranging from 6.0 to 7.2. Adding organic matter to the soil can enhance its growth.
Propagation can be achieved through seeds or cuttings. Seeds can be sown directly outdoors in early spring after the last frost, or started indoors six to eight weeks prior. Feverfew seeds require light for germination, so they should be surface-sown and lightly pressed into the soil without being covered deeply. For cuttings, non-flowering stems about 4-6 inches long can be rooted in water or a soilless mix.
The plant typically blooms from June through August, and harvesting flowers regularly can encourage continued blooming. For medicinal use, leaves can be harvested throughout the growing season. Flowers are best collected when three-quarters open or just beginning to fully bloom, as this is when essential oil content is highest. Harvested plant material can be used fresh or dried by hanging stems upside down in a cool, dry, and dark place.