How to Plant, Grow, and Care for Lithops (Living Stone Plants)
Lithops, more commonly called living stones or pebble plants, are unusual rock-like succulents. They are one of the easiest plants to care for once you understand their native environments. Horticultural expert Lorin Nielsen explains all you need to know about these unique plants.
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Have you ever browsed the succulent section and discovered a pot with nothing more than a pair of rocks in it? If so, you may have discovered lithops, a unique African succulent genus.
Sometimes called living stones or pebble plants, lithops are extremely drought-resistant and are widely popular in water-wise gardens. They can be grown both indoors and outdoors with the right light, but outdoor growers should be careful that they don’t get too much water.
The term lithops is both singular and plural, so don’t go searching for a lithop. This plant is quirky and fun, something different to mix into your succulent garden!
What is Lithops?
Lithops are fascinating little succulents. Commonly known as living stones, they are very sensitive to the extreme seasons of the year. Many species flower in the fall, which brings a great burst of color amidst all the oranges and reds of the season.
When you look at lithops plants, only a pair of fleshy succulent leaves with a crevice between them are visible. The majority of the plant is beneath the soil surface.
These succulents have window-like cells on the leaf surfaces that allow light deep into the plant to aid photosynthesis. The main taproot is the most important for the plant’s survival. But a series of finer roots also help draw in extra nutrition when needed.
Characteristics
Lithops succulents flower in late autumn or early winter, although some species flower in the spring or early summer. A single flower is pushed up from the crevice between the pair of leaves. Only plants older than three years (and sometimes five years) will produce flowers.
The lithops flower is daisy-like in appearance. Depending on the species, it can be anywhere from a half-inch to an inch and a half in diameter. It can be orange, white, or pale yellow. Some have a scent that is described as spicy-sweet.
These flowers will open in the early afternoon to soak in sunlight and allow for pollination. They close in the late afternoon before dusk. As lithops are not self-pollinating, they are reliant on insect pollinators or humans to produce seed.
Lithops Lifecycle
When the lithops flower fades, the center forms a seed capsule. This capsule does not open unless it’s been moistened. But once it does, rain droplets can cause seeds to bounce out of the capsule and land up to a foot away from the parent plant.
As the lithops seed capsule dries again, it will naturally close to protect any remaining seeds inside. If you are trying to harvest lithops seeds, you can simulate rain by using a dropper to drip water on the seed capsule until it reopens to remove the fine seeds.
After flowering has concluded, the plant will go dormant. During this time, it starts to form a new body. When it begins to grow again, the new leaf pair will emerge from the crevice between the old leaves.
Over time, the plant will draw its moisture and nutrients from the old leaves, transferring them to the new pair. The older leaves will thin out. Once they’ve become paper-thin and are devoid of moisture, they can be removed to reveal the new plant body.
Lithops may grow in size by creating two leaf pairs instead of a single pair, and can gradually expand to become a clump of small plants.
Types of Lithops
It’s estimated that there are at least 37 species of lithops, and around 145 varieties. More varieties are regularly discovered or bred by hybridization and are shipped bare root. Here are some of the most popular houseplant varieties.
Lithops aucampiae
Named after Juanita Aucamp, the woman who discovered this species, this plant originates in South Africa. It naturally grows in sandstone, chert, quartzite and ironstone-based soils, but can be grown in most sandy, extremely well-draining soils.
Most plants of this species tend to be in the red to red-brown range colorwise, and they produce yellow or white flowers. It is one of the species that most tolerate occasional incorrect watering, making it extremely popular amongst gardeners.
Lithops dorotheae
Another species from Southern Africa, this one was discovered by Dorothea Huyssteen, leading to its naming. Naturally growing on feldspar, sheared quartz and quartzite, it can adapt to other grit-filled soils as well.
This species has a creamy pale green coloring with a brown or darker green leaf surface, mottled with cream-colored speckles. It produces a yellow flower annually.
Lithops fulviceps
Originating in Namibia, this succulent prefers rocky areas and cold desert regions. It naturally prefers quartzite-heavy environments, although it can live on limestone slopes too.
The sides of the leaves are a greyish-green or yellowish hue with orange, brown, green, and sometimes cream-colored mottled upper surfaces. The leaf shapes are similar to kidney beans as they divide to flower, but form a neat oval when not flowering. They produce a white or yellow flower depending on the cultivar.
Lithops hookeri
Preferring quartzite and lava rock to grow on with some limestone, this is another South African stone plant with a marked stone-like appearance. It can grow quite large for a pebble plant with leaf sizes nearing two inches across at their widest point. Normally growing singly, it can form clumps of up to 10 pairs of leaves.
The upper surface of its leaves can range from brownish to red or pink tones, occasionally picking up bits of orange. The sides of the leaves are often a dull grey or greyish-brown, almost terracotta tone. Its flowers are usually bright yellow.
Lithops karasmontana
Depending on the species, this succulent will either mimic the grey and brown hues of local quartzite stones or will develop a brilliant red-orange upper leaf in some varieties. The sides are uniformly grey with a tinge of brown.
Its name refers to the Karas Mountains in its native Namibia, but it can also be found in South Africa. It produces a brilliant white flower with a yellow center.
Lithops lesliei
Found naturally in Botswana and parts of South Africa, this species is incredibly variable in terms of color, ranging from pale green to a rust or coffee coloration.
It often camouflages itself to match the color of the soil around it, making it difficult to see. It rarely rises more than a couple millimeters above the soil’s surface to further disguise itself. The yellow-flowered plants are often harvested for medicinal use in South Africa.
Lithops localis
A species that can tolerate a poor watering schedule or inconsistent habits, Lithops localis tends to be a uniform grey or green-grey color across most of its surface, giving it quite a stone-like appearance. Speckles of a darker grey hue dapple the flat top of the leaves.
Indigenous to the southern Karoo region of South Africa, it often grows amongst other rocks and shading shrubs to disguise itself from animals. Its natural environment gets most of its rainfall during the summer months, and thus it tends to flower in the fall.
Lithops optica
Another Namibian species, Lithops optica lives in an area that gets winter rainfall, making it one of the few varieties adapted to winter watering. The most popular variety of this plant is Lithops optica var. rubra, which is purplish-pink across its entire surface.
The thin-petaled flowers tend to be yellow or white and have slender petals. While the Rubra variety is brilliantly colored, others tend to be grey to grey-brown in coloration.
Lithops pseudotruncatella
From southwestern Africa, the truncate living stone is very distinctive. Its exterior leaf walls tend towards an even grey tone, but the upper leaf surfaces are dappled with cream, olive green, and rust hues.
One of the few species regularly subject to mealybug attack, this plant is otherwise a sturdy and long-lasting species. In its natural environment, it often lasts for months without any water, simply absorbing moisture from the air around it.
Lithops ruschiorum
Off-white, grey, or tan in color, this particular plant looks very much like a living rock. Some varieties are a pure cream color, whereas others range between tan or grey with darker stone-like streaking.
Namibia is home to this cultivar as well, and it lives most often in cold deserts or rocky regions in the wild.
Lithops salicola
The salt-dwelling living stone takes its name from the mineral-rich environment in which it naturally occurs. It can be found in both Namibia and South Africa and is somewhat tolerant of incorrect watering practices.
While it can’t tolerate freezes, the grey to grey-green leaves are more tolerant of dry, cool temperatures than some. It produces a bright white or yellow flower in the late summer to early fall. Royal Horticultural Society has given this species the Award of Garden Merit.
Lithops verruculosa
One of the more recognizable species, these flowering stones often develop distinctive red warts on their surface. Different cultivars can take on different colorations ranging from reddish in hue to a gray-green tone with the red warting.
The ‘Rose of Texas’ variety produces pink-tinged flowers, whereas others produce white or yellow flowers.
Lithops viridis
The green-rock plant is from a small portion of the Northern Cape province of South Africa and is extremely uniform in coloration. The sides are greyish-pink, grey-green, or pure grey with an upper surface that is a dark grey-green tone.
Producing yellow flowers with yellow or white centers, Lithops viridis is often only seen in cultivation in botanical gardens. The more greenish specimens are some of the most prized, as they look like pale green-grey nubs rising from the gritty soil.
Lithops Care
For the most part, growing lithops is a very hands-off process. They handle themselves quite well! But there are a few things about how to care for a lithops plant that you’ll need to know.
Light
In its natural environment, lithops is a full-sun plant. Flowering stones require enough sunlight to produce their colorful stone-like display. However, four to five hours of direct sunlight per day should be enough to keep your plant happy.
In coastal regions or where the temperatures are cooler, you may be able to leave it in direct sun all day long. Those who live in desert conditions or areas where it reaches excessive heat should place their plants in indirect light or afternoon shade.
Indoors, ensure it gets enough direct sunlight every day and that you regularly rotate your plant. Etiolation, an elongation or warping of the leaves, can happen if your plant isn’t getting enough sun. Color loss can also become problematic if your plant gets too little direct sunlight.
If your plant is indoors and in lower-light conditions over the winter months, slowly re-adapt your lithops to longer periods of light in the spring by gradually increasing its full sun exposure. This will prevent scarring or sunburn on the leaves.
Plants in warm climates or regions where it doesn’t drop below 50°F (10°C) can remain outdoors all winter long and will not need gradual exposure.
Temperature
The South African regions like Namibia (the natural habitat of lithops) rarely experience frost. This means that the plant has never adapted to colder temperatures. It really, really doesn’t like the cold.
Prevent exposure to frost or freezes. The cell walls in the thick leaves will rupture if it’s too cold. This will cause your plant to rot and die. Ideally, don’t allow your lithops to remain in conditions below 50°F (10°C), and never leave it outside below 40°F (4°C).
While the optimal temperatures for lithops are between 65°F and 80°F (18-27°C), these desert plants can tolerate intense heat and temperatures up into the 90s and 100s for short periods (32°C and up). However, they should be exposed to morning sun and afternoon shade in these conditions.
Water
The most difficult part of lithops care is watering. The plant is from an area of extreme drought. Less than an inch of water in a year is not unknown in its natural environment. The plant has adjusted to a life of water conservation in arid regions.
Almost the entire plant is devoted to storing water to sustain itself. Those fleshy, rock-like leaves are basically water tanks for the plant’s survival! Because of this, you need to water according to the time of year.
Spring and fall are the plant’s normal growing seasons and when it’s most likely to need water. During those seasons, limit your watering to once every ten days or less. Do not water unless the soil has completely dried out to four or five inches below the surface.
If your plant seems happy without water during the spring and fall, don’t water it. Chances are that it’s getting enough moisture from the humidity in the air. Many species of lithops draw the majority of their moisture from dew or humid air.
Rain exposure should be greatly limited, even in well-drained soil. As I mentioned, these plants are not accustomed to having much water, and too much will cause decay in the plant!
During the summertime, living stones go dormant during the summer heat. Only water them if the plant is becoming wrinkled. Water in the early morning, and give only a tiny bit of water to the area where your lithops grow.
Avoid watering during the winter entirely. Your plant will be in semi-dormancy, although sometimes a flower may linger into the early part of the winter months.
Soil
A well-draining, grit-rich cactus mix is ideal for most lithops plants. Their natural habitats range from sand to decomposed granite and rarely hold on to much water.
Don’t have access to a cactus mix? Don’t panic. Make your own by mixing 50% potting soil or compost with 50% grit material. Good options include pumice or lava rock, sand, decomposed granite, perlite, or other gritty materials.
Soils that hold too much moisture can cause root rot or spur the development of pest problems. Since their natural environment is quite harsh, they tolerate poor soil better than rich soils.
Fertilizer
As a general rule, fertilizing your lithops isn’t needed. These plants get almost no fertilizer in their natural habitats, like most other succulents.
However, some people do offer their living stone plant a little burst of fertilizer just prior to its normal blooming season to encourage flowering. If you opt to do that, use a heavily-diluted cactus fertilizer with a low-nitrogen, high-potassium formulation.
Just like watering, you want to fertilize sparingly, if at all. Avoid foliar fertilization, as it can cause sunburn on the leaves.
Repotting
Unless you’re dividing your plant, you may find that repotting is rare. Lithops can live for 40 to 50 years, and it’s not uncommon for someone to have their plant in the same pot for 10-20 years!
The most common reason to repot is to divide the plant if your plants start to take over the entire pot. Otherwise, you may want to place their lithops in a larger pot to develop a larger colony of plants.
Regardless of why you’re repotting, you will need a pot deep enough to handle the long taproot. A minimum of three inches is required, but five inches or even slightly deeper is better. This allows the taproot to grow without coiling around the pot.
Prepare a well-draining cactus potting soil, and plant your living stone plant with its leaf tops slightly above the soil’s surface. About a half-inch above the soil is fine. Be cautious with the root structure, as the taproot is essential to your plant’s survival.
Once repotted, you can place gravel or rocks around the soil surface to simulate the natural environment. Avoid transplanting it for at least another three to four years. If it was a division, wait even longer.
Pruning
Living stones or split rocks don’t need pruning. Since only two leaves are visible above the soil level, the plant will take care of itself.
At the most, you may rarely have to remove the papery remnants of older leaves of split rocks once the plants start to reabsorb all of their moisture and nutrients. Even then, the new leaves will spring up from the older ones, and the older leaves will slough off on their own.
Propagation
Most people propagate lithops from seed. To do this, you simply prepare a pot of soil as described above, carefully sprinkle your lithops seed over the surface, and cover it with a fine layer of sand. Keep the sand lightly moist until germination occurs, and gradually reduce watering for your baby seedlings.
These plants can also be propagated by division of a parent plant. If you have a cluster of plants, you can carefully remove it from its pot, gently dusting off the soil around the roots. Examine the root and leaves to decide where to cut, then use a sterile razor blade to neatly remove the leaf pair with a good amount of taproot still attached.
Including any of the other finer feeder roots is less essential, as these will quickly regrow. But your lithops leaf pair will require some of the taproot to survive. Once separated, repot as directed.
Common Problems
The majority of problems with the living stone plants come from overwatering. However, a few pests may be tempted by the juicy leaves, and there are a few other issues that might strike your plant.
Growing Problems
Etiolation is a plant basically stretching and warping to reach sunlight. Living stones are prone to etiolation. Instead of lying flat against the surface of their soil, they will rise above it and bend or twist so that the tops of the leaves are angled to the sun.
If your plant appears to be suffering from etiolation, it needs more consistent direct sunlight. Gradually reintroduce your plant to more light over time. During its next dormancy cycle, the new growth should form against the soil level again.
Dessication or wrinkling of the split rocks leaves can occur when your plant gets thirsty. If it starts to develop a raisin-like surface, give your plant a drink. It should re-plump itself up within a day or two. At the same time, avoid overwatering as excess water can be a problem, too.
Scrapes to the leaf surfaces can cause brownish or whitish scars that look very similar to a scratch on human skin. These scars will remain until the plant has developed a new leaf pair. But those leaves wither away as the moisture is reabsorbed into the plant.
Pests
Most pests are likely to ignore lithops the majority of the time. However, a handful can act to damage your plant if the opportunity presents itself.
Spider mites are the most likely problem of lithops growers. Most often they will live in the crevice between split rocks leaves, or hidden between an old leaf and a new one. They cause white spots of scar tissue on the plant’s surface, and they thrive in dry environments.
If you encounter spider mites on your plant, consider using a product like neem oil along the sides and in the center crevice of the plant. The mites rarely attack the upper surface of the leaves, so this should be enough to protect it.
There are a few other pests that can attack your plant, but these are opportunistic pests. They prefer other plants as a general rule, but if your living stones make an appealing target, they may strike. Here’s a short list:
- Thrips: If your pebble plants are shedding older leaves, thrips can live between the older thinning leaves and new ones. They can cause dark scarring to the newer leaves. Use insecticidal soap to eliminate these on your lithops and other surrounding plants.
- Scale Insects or Mealybugs: Mealybugs are a form of scale insect, and both regular scale and mealybugs will attack many cacti and succulent plants. Gently scrape them off and apply insecticidal soap to the plant’s exposed surfaces.
- Aphids: Cactus aphids may be lured to your lithops and its juicy leaves. Again, insecticidal soap should eliminate these pests.
- Mice: Surprisingly, mice find lithops plants to be attractive food sources. Use good mouse traps to keep them out of your house, and consider placing a fine mesh cloche over potted outdoor specimens.
Generally, the only pest that most people will ever see on their lithops is spider mites, because the optimal conditions for other pests aren’t usually met.
Diseases
The vast majority of plant diseases have little to no impact on lithops. Since they grow in sandier soils, they are not subject to most soilborne fungal diseases, and they do not typically develop powdery mildew or other above-ground fungal diseases.
However, they are susceptible to rots caused by overwatering or damage to the leaves. An excess of water can cause the fleshy leaves to swell and crack or burst, leaving them open to bacterial infection. Scrapes or cuts on the leaves can also leave them at risk.
Generally, as long as you are careful about not scratching your pebble plants and limit your watering to only when it’s most necessary, you will not experience any plant diseases.
Frequently Asked Questions
Do lithops split every year?
Yes, this is normal. What most people are experiencing is the process of lithops forming new leaf pairs. In the process, the old layers are shed, much like a snake sheds its skin.
What do overwatered lithops look like?
Yellowing is a sure sign of an overwatered lithops. In addition, a mushy texture may mean that it’s starting to rot, a common issue if it’s been overwatered for too long.
What is Blue Witchford lithops?
There are a number of unusually-colored plant seeds sold online, and Blue Witchford lithops is one of those. In most cases, these are fakes.
It’s believed that the images shown online of it are heavily photoshopped. In fact, they aren’t even of a lithops plant at all. They’re images of Pinguicula esseriana that have been colorized blue to sell seeds by scammers.
Are lithops poisonous?
The ASPCA has it marked down as non-toxic to dogs or cats. So the lithops plant itself may not be toxic. Whether or not it tastes good may be a different matter. The flowers themselves can smell spicy-sweet, but there are few reports as to the flavor of the leaves, suggesting it’s not an ideal food source. Still, they should not be poisonous. If you are concerned, it’s best to check with your doctor or veterinarian. Better to be safe than sorry!