Cudweed is a native North American plant that can take on several different forms and grow in different types of areas. Most are a broadleaf annual, though some establish themselves in mild climates where they can be a biennial weed as it survives two full growing seasons.
Most cudweed species are annuals. However, purple cudweed, known by its scientific name of Gnaphalium purpureum, can be either a winter or summer annual or biennial if it matures into a second year. Creeping cudweed, whose scientific name is Gnaphalium collinum, is perennial weed. Everlasting cudweed’s scientific name is Gnaphalium luteo-album tends to be a nursery and landscape weed. And Gnaphalium stramineum, which is more commonly known as cotton batting, is the bane of many homeowners’ existence as it can overrun turf. Most cudweed plants have sparse branches and grow up to 20 inches tall. Flowers on this weed are densely packed, spiked in shape, and arranged on the stem at the base of leaf stalks. Leaves are usually green above but can be a pale green to almost white on the undersides. Foliage often appears white and wooly.
Cudweed is found in most areas of the United States, though it is especially prevalent in the southeastern parts of the United States. It tends to prefer meadows, roadsides, railway embankments, sandy areas, and wastelands. Certain types of this weed grow extensively in lawns and landscapes and can be challenging to manage in thin turf or landscaping. Some thrive in sun-baked, desert-like climates. They are also found in parts of Norway and Finland where they grow in colder climates.
There are a number of long-standing medicinal uses for cudweed. It has been used to treat mouth and throat diseases and has astringent properties. Medicinally, the leaves of the cudweed are added to boiling water to create an astringent mouthwash. Certain types of cudweed foliage are used as an addition to salads and smoothies for a unique, bright, sharp flavor. However, in some areas, this weed can tend to have a buildup of nitrates, which can be toxic to cattle and livestock in pastures. It reproduces by seed, but it rarely grows in the same places twice.
Weed control for this plant usually consists of prevention. A well-maintained turf or landscape makes cudweed unable to compete for resources, and it is therefore easily strangled out. Therefore proper mowing, watering, fertilizing, and maintenance will be the best method to combat the spread of cudweed. Hand pulling individual weeds is not recommended as it is not effective. Mechanical removal tends to result in the plant growing back immediately. Once it has become established in lawns and landscapes, the best way to eradicate it is to utilize professional broadleaf weed control measures. Multiple repeated applications of broadleaf herbicides containing glyphosate may be required. Because it is a non-discriminant herbicide, it can damage surrounding plants when applied, so carefully controlled apps 7-10 days apart are highly recommended for eradication of cudweed in lawns and landscapes.