Rocks differ in shape, color, size, and texture, and plants that look like rocks are no different. Many plants have adapted to survive in their natural habitat by looking like rocks to protect themselves or their recourses. Plants that look like rocks do so as a disguise to avoid being eaten. Other plants form large rock-shaped tubers as a way of storing water
These adaptations are both interesting and beautiful. Plants that look like rocks make for interesting talking points when added to the garden or kept as indoor plants. With many small succulent plants resembling rocks, it is easy to keep a collection indoors and add larger varieties to an outdoor garden.
Related: 7 Plants That Look Like Coral
1. Climbing Rock Plant
Stephania perrieri is better known as a climbing Rock plant and is a member of the Menispermaceae plant family. This family of plants is comprised of around four hundred and forty species. Climbing rock plants are native to Australia and southern Asia and are used as traditional medicine.
The common name of the climbing rock plant is due to the caudex of the plant growing in the shape of a rock or a clump of rocks. The caudex or basal stem of the climbing rock plant can grow as large as two feet high and one foot across. This caudex is adapted to store water for the plant during the dry month of the year when the leaves die back.
Climbing rock plants’ heart-shaped leaves grow from the caudex on long vines attaching themselves to nearby rocks or trees for support. The leaves are light green, and the vines can be shaped and trellised to form displays or encouraged to vine along a screen. When the vines die back in winter, the climbing rock plant needs minimal watering.
2. Elephant’s Foot
Elephant’s foot (Dioscorea elephantipes) is also called Hottentot bread and is native to the semi-desert areas of South Africa. Elephant’s foot is a member of the Dioscoreaceae plant family, which includes more than seven hundred species.
Elephant’s foot is a deciduous plant that loses its heart-shaped leaves in the hot, dry summer months to preserve moisture. The impressive caudex with its deep fissures of the elephant’s foot resembles the rocky slopes it grows on.
Like its distant relative, the yam, the elephant’s foot caudex is edible, giving rise to the name Hottentot bread. The caudex of an elephant’s foot grows significantly bigger than a yam, reaching a height of three feet and a circumference of more than ten feet. Elephant’s foot is a slow-growing plant but can reach an age of up to seventy years.
3. Sand Dollar Cactus
The sand dollar cactus (Astrophytum asterias), also called sea urchin cactus or living rock, belongs to the Cactaceae family. These plants are native to the United States and Mexico but have spread across the globe as cultivated plants, with hundreds of varieties available.
These round, rock-like plants are slow growing, and the smaller varieties, known as day-flowering cacti, are ideal for indoor cultivation. In its natural habitat, this cactus is endangered, but most plants purchased at nurseries are grown from seed and ensure the continuation of this plant.
The round body of the sand dollar cactus is divided into seven to ten ribs or sections, causing the resemblance to a sea urchin. Typically, the sand dollar cactus grows to a height of one to two and a half inches with a diameter of two to six inches. Sand dollar cacti are slow growing and bear yellow flowers that produce a green seed-filled fruit.
Related: 5 Plants That Look Like Cactus
4. Optica Stone Plant
The optica stone plant (Lithops optica) also goes by names like the LüDeritz Stone plant and is a member of the Aizoaceae plant family. The optica stone plant is endemic to a very arid region of Namibia, where the plants blend into the rocky environment.
Optica stone plants are generally referred to as living stones with colors that range from grey-green to light brown or even purple or red. The optica stone plant gets its name from the round window shape at the top of the leaves that grow in pairs.
The plants produce new leaf pairs with age to replace the original leaf pair. The older leaves shrivel and die over time. Counting the number of dead leaves can be used to age a plant that can live up to ninety years. Older plants also divide and form clusters of new plants making up little colonies of up to ten new plants.
Related: 5 Plants That Look Like Succulents
5. Button Plants
Button plants (Conophytum) also go by names like cone plants or dumplings and belong to the Aizoaceae plant family. The Conophytum genus consists of a hundred species that are native to South Africa and Namibia. Plants range from grey-green with dark green spots to unmarked reddish plants.
Button plants look like small pebbles when they grow in a colony or like small stones when the variety grows as a singular plant. The plant body is made of succulent leaves that merge to form a single spherical or oval-shaped plant. Button plants produce one to two small yellow flowers each year.
The button plant prefers to grow in rocky crags and outcrops rather than in soil. Plant size can vary from a quarter inch to two inches and are very slow growing. Some varieties can take up to fifty years to grow to the size of a walnut.
6. Horse’s Teeth Plant
Horse’s teeth plants (Haworthia truncata) belong to the Asphodelaceae plant family. These succulent plants have a rectangular shape with a square top that creates the impression that the plant was cut. The plant is often half-buried in its natural habitat, only presenting the leaf tops.
Horse’s teeth plants resemble small grey to grey-green rock crags. Horse’s teeth plants are small succulents growing to a height of an eighth of an inch wide, four inches wide, and three to five inches tall.
Haworthia plants tend to grow in a spiraling cluster formation. Horse’s teeth leaf tips have a leaf window. This is s translucent section that assists with the plants’ photosynthesis. The horse’s teeth plant propagates by producing plantlets or pups at the base of the mother plant.
7. Pearly Moonstones
Pearly moonstones or sugar almond plants (Pachyphytum oviferum) are members of the Crassulaceae plant family. This family of plants, also called the stonecrop family, has a unique form of photosynthesis called Crassulacean acid metabolism.
The pearly moonstone plant is native to Mexico, where the preferred habitat is rock cliffs. Moonstone leaves are shaped like oval pebbles. The color ranges from blue-green to very pale purple, and the leaves are arranged in a rosette formation around a short stem.
Moonstone leaves are up to two inches long, slightly more than an inch wide, and almost an inch thick. You can propagate new plants from these plump individual leaves. Moonstone plants produce flowers on a tall flower stem in winter. Flowers are bell-shaped and have white outer petals with bright red inner petals.
Kambroo (Fockea edulis) is another plant commonly called Hottentot’s bread. This member of the Apocynaceae plant family is native to South Africa and Namibia and is adapted to grow in arid conditions.
Kambroo forms a large tuberous root structure with a diameter of around two feet which may be partially buried. Branches grow from this rock-like tuber and produce oval-shaped leaves. The trailing branches grow up to thirteen feet long and climb against rocks or plants for support.
The rock-shaped tuber of the Kambroo plant is edible and has a slightly sweet flavor. It was traditionally eaten by the Khoi people as food and to provide moisture, as the root stores water for the plant. Both male and female plants are needed in order to produce viable seeds for reproduction. The flowers of the Kambroo plant are pollinated by fruit flies.