Common names:  Ragged robin, cuckoo flower, meadow campion 

Family: Caryophyllaceae

Life form: Herbaceous perennial

History & Introduction

Ragged robin (Silene flos-cuculi) is native to Europe and western Asia, where it primarily grows in wet meadows. It gets its name from the ragged appearance of its flower petals. In its native range, it is culturally significant and was even mentioned in Shakespeare’s Hamlet. Sadly, it is considered to be near threatened in England due to habitat loss.

Ragged robin was introduced to North America in the mid-19th century, arriving in ship ballast and spreading further via the horticultural industry. It is now present along the East Coast, the Midwest, and the Pacific Northwest. It is invasive due to its tendency to form monocultures that displace native plants.

Identification & Biology

Ragged robin is a member of the carnation family, Caryophyllaceae. This family contains its native lookalike, the fire pink (Silene virginica), a plant with vibrant red flowers that lives in poor soils. In contrast, ragged robin has pink flowers and thrives in moist conditions. In North America, it may grow in roadsides, wet meadows, and floodplains. It blooms between May and August before dying back to a leafy rosette in winter. As a short-lived perennial, individuals live for 3 to 4 years.

FORM: An herbaceous perennial reaching a maximum height of 2.5 feet. The stems are lined with small hairs that make them rough or sticky. Stolons may also be present, allowing for lateral growth.

LEAVES: There are two distinct leaf forms. A rosette of oblong, basal leaves is present at ground level, while thinner, opposite leaves grow along the upper stems. Both leaf types are dark green.

FLOWERS: These have five deeply lobed petals whose raggedness and bright pink color make them easily recognizable. Occasionally, they are whitish. Like other members of the genus Silene, ragged robin’s sepals are fused and form a tube-like calyx. 

FRUITS: These are small, dehiscent (self-opening) capsules reaching 6 to 10 millimeters in length. When ripe, they are dry and open at the top to release thousands of minuscule seeds.

Damage & Concern

Ragged robin outcompetes native plants and may occasionally form monocultures that threaten native plant communities. In Pennsylvania, it has been observed displacing rare species in riverside scours. On Long Island, ecosystems like coastal plain ponds may be at risk. There is also limited research suggesting that this plant’s compounds are mildly toxic to fungi and soil microbes (Maliński et al. 2021).

Aside from spreading where it is already established, horticultural escapes may allow ragged robin to spread to new regions. Its sales are prohibited in Connecticut, but remain legal in most of North America. 

Management

Manual removal is the most ideal strategy for managing ragged robin. This is most effective in spring, or before the plants have set seed. Deadheading may also be effective, and may reduce soil disturbance that could facilitate future outbreaks or promote invasion by other invasive species. Revisiting the managed area in the following years is encouraged as seeds remain viable for up to five years. Plants may also re-sprout from root fragments or stolons if they are not entirely removed.

Other management strategies include smothering and chemical control. Smothering with weed fabric may be preferable in dense patches, as hand-pulling is laborious. Chemical control may also be effective, but is less preferred and may also kill native vegetation

Monitoring or Reporting

Ragged robin is a Tier 2 species in LIISMA and a priority for early detection, rapid response, and eradication. If you find this species, we invite you to upload your observation to iMapinvasives or iNaturalist as soon as you notice it. Your photos help us detect emerging invasive species and stop the spread. You can also upload your observation to our website here.

iMapInvasives is a network for invasive species reporting, allowing concerned parties like LIISMA to discern where invasive species may be popping up, or their geographic extent. Similarly, iNaturalist functions as a biodiversity reporting platform for all kinds of living things—native or non-native—and can help anyone identify and share what species are inhabiting a given area. 

If you are interested in playing a bigger part in protecting our local flora and fauna, consider joining LIISMA’s Invasive Species Spotter Program! This program teaches you how to spot emerging invasive species as they arise, giving you valuable detection skills against occurrences of invasive species that were not previously on LIISMA’s radar.

Written by Matt Stanton LIISMA Summer 2026 Intern