The 60 species of Grindelia, a North American perennial, are characterized by the presence of rigid, bristlelike spikes (known as phyllaries) just below the flower petals. Many species have common names that refer to a gummy substance that forms on the flower heads. In some parts of the world, children use this substance as chewing gum. Although the herb didn’t come into use in Western medicine until the latter part of the 19th century, Native Americans traditionally used grindelia to treat respiratory and skin conditions.
Common Names: Asthma Weed, Grindelia, Gum Plant, Gum Weed, Tarweed
Description: Coarse, shrublike perennials or biennials, up to 3 feet tall; slightly toothed, spade-shaped leaves; numerous sticky, yellow disk flowers surrounded by ray flowers, occurring in heads
Hardiness: Varies according to species
Flowering: Late summer
Parts Used: Flowers and roots
Range/Habitat: Dry prairies from Saskatchewan to Mexico; most species occur west of the Mississippi
Grindelia can be used externally to relieve skin irritations caused by poison ivy and poison oak, as well as burns. The yellow flowers produce a sticky resin that contains an anesthetic constituent. Grindelia squarrosa is said to be especially effective for this purpose. To make a poultice for poison ivy or poison oak rashes, boil 1 ounce of the plant’s leaves, stems, and flowers in 2 cups of water for 10 minutes. Cool, strain, and soak a cloth in the cooled liquid, then apply the cloth to the affected skin.
Taken internally, grindelia has expectorant and antispasmodic properties. The herb helps rid your lungs of excess mucus while relaxing and dilating your airways. It has been used to treat bronchitis, asthma, and whooping cough, although it can be toxic if taken in large doses.
How to grow it
A coarse, shrublike plant without ornamental qualities, grindelia is cultivated almost exclusively for medicinal purposes. Grow the herb in full sun and moderately rich, well-drained soil. Start with seeds, cuttings, or divisions. If starting with seeds, sow them outdoors in fall and cover only lightly with soil. Or sow them in a cool greenhouse in early spring, then transplant the seedlings to the garden when temperatures have warmed. Harvest leaves and flowering stems when the plant is in full bloom. Plants can be propagated by seed, cuttings, or division.