Calyptocarpus vialis

creeping Cinderella weed


Calyptocarpus vialis

Less. 1832

pronounced: kal-ip-toe-KAR-puss VEE-uh-liss

(Asteraceae — the daisy family)

synonym — Synedrella vialis

(Less.) A.Gray 1882

pronounced: sy-nee-DRILL-uh VEE-uh-liss

common names: creeping Cinderella weed, straggler daisy, horseherb

Calyptocarpus is derived from the Greek καλυπτρα (kalyptra), a woman’s veil, and καρπος (karpos), fruit – with hooded fruit. Vialis is Latin for ‘of the roads’, indicating that this is a plant of the roadside and of waste places. I have been unable to trace the origin of Synedrella, but saying the word aloud will explain the ‘Cinderella’ of the common name.

This is an annual herb with sprawling stems native to the southern parts of the USA and to Mexico. It is now naturalized in many tropical and sub-tropical areas of the world. The patch photographed was by the roadside outside the Parks and Wildlife building in Hurst Street, Picnic Bay. The stems are thin and weak, tending to sprawl over the ground. They are green or reddish in colour and rough to the touch, growing upright at first, but falling to the ground as they lengthen. Adventitious roots are formed at the nodes. The plant will normally keep low to the ground, but, if it finds something to sprawl over, can grow up to about 40 cm high.

The leaves are opposite, with stalks up to a little over 1 cm in length. The blades are ovate to triangular, up to 4 by 2.5 cm in size, with an acute tip. They have short hairs, and margins notched with small, forward-pointing teeth.

Small bright yellow ‘daisy’ flowers (5–10 mm across) are produced in the leaf axils. They are usually solitary, but sometimes a few can be found together. The flower heads of this plant are some of the smallest that have both the disk and ray florets characteristic of the daisy family. The pappus has 2 short ascending awns. Fruits are achenes, small and burr-like.

Depending on your point of view, this plant is either a pest, or a welcome, shade-tolerant groundcover that tolerates moderate foot traffic. It often shows up in shady patches of lawn. It grew in popularity in the southern parts of the USA when there was a renewal of interest in native plants there towards the end of the 20th century, and seed for planting was occasionally available commercially. Gardeners liked it because of its ability to thrive in the shade, that it needed no mowing or watering, and that it kept its colour for most of the year. It also gives the bonus of attracting small lawn butterflies to its flowers.

In a blog I read on this species, however, I found that most gardeners in that part of the USA now regard it as a pest. Some complained that the burrs stuck to the soles of shoes and were tramped not only all over the garden, but into the house. Many complained of the lightning speed at which it spread, that it was difficult to remove, and choked out other plants. One blogger accused it of trying to take over the whole garden. Most agreed that it would be very invasive if not kept in check, but also that it was a good plant for quick revegetation of bare areas of the garden.


Photographs taken in Picnic Bay 2011
Page last updated 27th October 2018