Plant Common Name
There are approximately 45 species in the genus Herniaria. They are mostly low-growing, mat-forming annuals, biennials or perennials. Commonly called the ruptureworts, they are naturally distributed across Europe, South Asia and Africa and naturalized in other areas, including South America. In old times, plants in this genus were believed to help with hernias and ruptures, hence the common and botanical name.
Herniaria have long, slender taproots and may be bushy and spreading or climbing. They are primarily foliage plants with densely packed small, rounded to oblong leaves that are opposite of each other on the lower stem and alternate to each other on the upper stem. The flowers are small, insignificant and produced in tight clusters. Small, hard, reddish-brown fruits follow the flowers.
The most commonly grown species of rupturewort is Herniaria glabra. This pretty low-growing perennial is popular for containers, filler between pavers or as a turf substitute in low traffic areas. It is an evergreen perennial in warmer zones and used as an annual in colder locations. Hairy rupturewort (Herniaria hirsute) is an annual from Africa. It has gray-green leaves that are densely hairy. This species produces lots of seed and is considered invasive in some areas.
Only a few species of Herniaria are cultivated. Generally, they prefer sunny to partially sunny locations and are tolerant of most soils as long as the have excellent drainage. Most are sensitive to cold and equally intolerant of extreme heat and humidity. They are best grown as annuals or container plants. Where hardy, they are ideal for rock gardens and walkway or bed edges.