In the 1970s, a man named Gary Dahl became a millionaire selling Pet Rocks. This "toy" was literally a smooth gray stone that came nestled into a straw bed inside a cardboard box perforated with "breathing holes," along with a 32-page tongue-in-cheek instruction manual for its proper care and feeding. While the original Pet Rock was quickly discontinued, you have the opportunity to adopt a much better "pet rock" of your own, specifically a succulent commonly referred to as "living stones."
Living stones ( Lithops) are tiny yet attention-grabbing, and their maintenance needs are only slightly more burdensome than those of the classic Pet Rock. That means Lithops are a perfect resilient plant for forgetful plant-owners, no 32-page care manual required! If you're looking for an adorable houseplant that thrives on neglect, look no further than living stones.
Quick Guide to Lithops
Living Stones' Physical Appearance
There are 37+ species and 145+ varieties of living stones, which come in a variety of colors and patterns, but all have virtually the same growth patterns and care needs. The color range includes red green purple, grey, pink, and other shades, either uniformly or with mottled, veined, dotted, or other markings.
These plants are all structurally similar. They grow two leaves joined at a groove, so that from above they resemble the imprint in the soil from the footstep of a cloven-hoofed animal. They are virtually stemless, the two leaves growing flush with the ground and never getting any taller.
In drought, the visible leaves of living stones may die off, leaving only the roots below the soil, which will stay dormant until the next rainfall. The leaves also die back in the fall, when the plant is about to produce its new leaves.
Many living stones flower in the late fall or early winter, with a single blossom emerging from the crevice between the two leaves. Some are even scented.
Note: After flowering the plant produces a pair of new leaves from the groove between the leaves. The older leaves will dry up and die. At that point, the plant begins its winter dormancy.
Growing Requirements for Lithops
Where to Plant a Lithops Succulent
Outdoor Placement
Living stones originate in arid regions in southern Africa. This means they are accustomed to extremes. They prefer high heat, lots of sun, and almost no water. Because they are so small and therefore have fairly shallow roots, and they are accustomed to deserts with rocky and sandy soil, they are a perfect choice for rock gardens or other areas with "poor" soil.
Because they are so drought-tolerant, and typically require no water at all during their winter dormancy, they may not survive in a climate that gets much rainfall during the winter, especially if they are planted in soil rich in organic matter, which retains water.
Note: Unless you live in a place with rather dry winters, planting your living stones in a pot that can be moved to a dry spot for winter may be a better option than planting them in the ground.
Indoor Placement
While they do great in desert or greenhouse temperatures, can be grown inside your home as long as you keep the temperature in the mid-sixties or higher. You'll want to place your lithops in your sunniest windowsill, making sure they get a minimum of five hours of sunlight each day.
Pet Access
Lithops are nontoxic and are considered safe to grow in households with small children and pets. For more suggestions for safe houseplants, check out our round-up of pet-safe succulents.
Living Stone Plants Container and Soil
Although most of the plant is underground, Lithops are such small plants that they have fairly shallow roots, so it is important to pot them in a shallow planter. Just a few inches of potting mix is plenty. This is especially important for Lithops, even more than most succulents, because they are so drought-adapted.
Note: A pot that is too large and contains too much potting mix will take too long to dry out, which can cause your Lithops to rot.
If you have a typically-proportioned pot you really want to use, you can try using our " pot in a pot" method. To do so, you would need to find a plastic pot that is shallow but nearly the same diameter as the decorative pot you want to use. Plant your living stones in the plastic pot, and then nest it inside the decorative pot.
You can put rocks inside the decorative pot to rest the plastic pot on. However, if your decorative pot doesn't have a drainage hole, make sure to remove the plastic pot before watering, and let it drain before returning it to the decorative pot. This way the water doesn't accumulate in the bottom of the decorative pot.
Note: The excess humidity from the water sitting in the bottom of the pot, slowly evaporating, can kill your living stones.
Commercially available cactus/succulent-specific potting mixes will work okay for Lithops, but making your own potting mix is much better for your plant as well as cheaper.
We recommend a different ratio of ingredients for living stones than most succulents (with less organic matter) because they thrive in poor, rocky soil. You don't have to be strict about the ratios, but for Lithops we recommend:
- One part potting soil, ideally a cactus blend,
- One or two parts coarse sand, and
- Two parts gritty amendment (such as perlite, pumice, or gravel).
It may seem strange to give a plant so little organic matter, but imitating a plant's natural environment is the best way to keep your succulent happy and healthy.
Watering The Living Stone Plant
Originating in South African deserts means that Lithops' capacity for handling drought is extraordinary, almost supernatural. The average annual rainfall where most Lithops species live is less than 20 inches, while some species survive on less than four inches, and a few rely exclusively on fog as their source of moisture. Virtually the entire body of the plant is devoted to water storage.
In that context, it should come as no surprise then that living stones have extremely minimal watering needs. Outdoors, you are likely to find that they do not require any water at all to supplement the natural rainfall. Indoors, as you would expect, the biggest problem faced by most lithops is overwatering.
Note: Typically indoor lithops go dormant from the late fall to early spring. Outdoors, they may also go dormant in the summer. They require little to no water during their dormant period(s).
After the new leaves begin growing in the fall, we recommend not watering at all until spring. Watering too late into the fall can kill your living stones, because that is when the old leaves should dry up and die, which allows the new leaves to grow. Only water during the winter if the new leaves are also becoming very shriveled.
During the living stones' growing seasons, we recommend watering only on an as-needed basis, using the "soak and dry" method.
For more information on the "soak and dry" watering technique, among others, check out our complete guide to watering succulents. It includes a tracking card for watering, fertilizing, and other succulent care.
Note: Because your living stones may need watering only a few times a year, it's a good idea to keep track, so that you don't forget entirely.
Fertilizer and Maintenance
Lithops are accustomed to poor, rocky soil, so they don't need a lot of fertilizing. If you repot your living stones when you bring them home, don't bother fertilizing the first year, as the fresh soil will have plenty of nutrients. In subsequent years fertilizing once, at the beginning of the spring growing season, is plenty.
When you do feed your living stones, use a liquid fertilizer, preferably organic. If you are using a chemical liquid fertilizer meant for houseplants but not succulents specifically, dilute to at most half-strength (quarter-strength is best).
As with all succulents, you want to avoid any fertilizer that is imbalanced, in the sense that it has a higher proportion of nitrogen than the other elements. Living stones have very minimal leaf growth, so they need more potassium than nitrogen.
If you're using an organic fertilizer formulated specifically for cacti or succulents, follow the package instructions regarding any necessary dilution. For more information, check out our comprehensive guide to fertilizing succulents.
Note: Lithops don't typically need any maintenance other than watering and fertilizing. You can remove the dry husks of the old leaves in the spring, if they haven't fallen off on their own.
Propagation
Lithops are not as easy to propagate as other succulents. They don't produce offsets, and don't have stems or leaves that can be easily propagated. There are two ways to grow new living stones.
One option is to grow them from seed. However, this is a laborious process - they may take as long as a year to sprout.
You can generate your own seeds if you have multiple living stone plants. In nature, living stones require rainfall-assisted cross-pollination to reproduce, they cannot self-pollinate, so if you want seeds you'll have to help.
Note: After they flower, you can use a cotton swab to transfer pollen from the flower on one plant to the other. Then harvest the seed pods that form.
Occasionally, in the fall, when living stones dry out and die back, allowing the new leaves to grow from the groove in the center, you will have an opportunity for propagation.
Sometimes instead of only growing one new pair of leaves, like normal, a healthy, mature Lithops will multiply on their own. In other words, they will produce two pairs of leaves instead of one. You can divide these to grow two new plants.
To divide your multi-headed Lithops, first remove it from the soil. Use a sharp, sterile knife to divide the two pairs of leaves, making sure each plant has roots attached. Allow them to cure, then replant. Check out our propagation guide for more detailed tips and techniques.
Common Living Stones Problems
Like most succulents, living stones are pretty bomb-proof. There isn't a lot to worry about, as long as you're meeting their basic needs. However, there are a few things to keep an eye out for, in order to ensure your plant stays healthy.
- Wilting, mushy, discolored leaves: You are overwatering your plant. Remember, it will probably only need watering a few times each year.
- Stretching: Living stones have essentially no stem, the leaves rest directly on the soil. If you notice that your plant has grown a little leggy, that is a good indication that your plant is getting inadequate sunlight.
- Scale: Living stones don't have all the little nooks and crannies common to most succulents, which means they're much less susceptible to being infested by the little critters that like to hide in them. However, if you notice flat, brown, immobile spots on your living stones, it could be scale.
- Brown patches on leaves: While living stones love a lot of sunlight, they do need to be transitioned gradually if you're moving them from more limited sunlight to lots of direct sunlight. Making the transition too quickly can cause sunburn.
- Leaves are dying (brown, dry, and crispy): Is it autumn? If so, this is part of these plants' natural life cycle.The old leaves have to dry and die off in order for the new leaves to develop. Ignore it. If the leaves are drying out during other times of year, it probably needs a drink of water.
If your succulent is having these issues, or any others, check out our guide to diagnosing and fixing problems with your ailing succulents.
Being a Good Plant Parent to Your Living Stones
Even better than a pet rock, living stones make a wonderful companion. They don't bark at night, pee on the floor, or need food and water daily. All you have to do is give them a warm, sunny windowsill, and water far less frequently than you think you need to. Living stones are truly the ideal pets for forgetful owners.
