Conophytum is a genus of about 110 succulents that belong to the Mesembs plant group. The name “Mesemb” is derived from the old family name Mesembryanthemaceae, which today belongs to Aizoaceae. The species is native to South Africa and southern Namibia and typically occurs in dry and semi-arid winter rainy areas. They are commonly known as button plants, cone plants, dumpling plants or live pebbles.
The first specimens of this genus were collected by the Scottish botanist Francis Masson in 1776 and sent to the Royal Botanical Gardens in Kew. The plants were first described by Adrian Hardy Haworth in 1821. He described two different species, Conophytum obcordellum and Conophytum obconellum, which were later combined into one species, Conophytum obcordellum. The genus was officially recognized and formally described by Nicholas Edward Brown in 1922.
The genus is sometimes incorrectly referred to as Conophyton, a generic name proposed by Adrian Hardy Haworth in 1821. The genus name “Conophytum” is derived from the Latin “conus” meaning “cone” and the Greek “phytum” meaning “plant,” and refers to the fused, cone-shaped leaves of most species.
Conophytums are dwarf plants that usually form dense clusters of pairs of leaves, but some species are solitary. The bodies consist of two fleshy, partially or completely fused leaves and are between 0.6 and 5 cm (0.25 to 2 in) tall. They can be bilobed, spherical, tubular to conical, ovoid or cylindrical and have a very smooth to hairy or slightly rough epidermis that is sometimes mottled, lined or fenestrated. Plant colors range from shades of green and blue to red and brown. Conophytums can be divided into day-blooming, dusk-blooming and night-blooming species. Most of them bloom from late summer to autumn. The flowers are small, daisy-like and in a wide range of colors with yellow or orange centers.
Some Conophytum species are confused with Lithops. Their conically connected leaves and petals, which are fused into a basal tube, distinguish them from most other mesembs.
Growing conditions for Conophytum
Conophytums are usually grown in containers where they spread slowly. These succulents are ideal for growers with limited growing space. Conophytums also grow well in rock crevices.
Most Conophytums require bright light but don’t like too much direct sun. To avoid sunburn, place them in an area where they will receive full sun for a few hours during cooler times of the day. At the end of the dormant period, increase sun exposure gradually over several days to avoid shock to the plant. The plants stretch when they need more light.
Conophytums grow best in porous soil mixes that allow water to drain quickly. Use a commercial potting mix specifically formulated for growing succulents or make your own.
High temperatures are not a problem for Conophytums, but they can be damaged if the temperature drops below 32°F (0°C). If you live in colder areas of the world where winter temperatures drop below freezing, it is best to grow these plants in containers that can be brought indoors.
Conophytums measure up to 60 cm (2 feet) in diameter in habitat, but in culture they are usually grown in pots about 5 to 10 cm (2 to 4 inches) in diameter.
General care for conophytum
Like all Mesembs, Conophytums also have a specific growth and rest period. They grow actively from fall to winter and go through a dormant period from spring to summer during which the existing leaves dry out and protect the new pair of leaves in a papery covering. During this time, the plant resembles a pebble, hence the common name “living pebble.”
When Conophytums are dormant in the spring, they require little or no water. In the fall, when plants begin to grow, it is safe to water deeply and allow the soil to dry before watering again. If the leaves begin to fold during active growth, your conophytum needs water. Too much water can cause root rot or produce a new pair of leaves at the wrong time of year.