Lithops are one of the most unique houseplants you can grow. Also called living stones, their crazy-cool appearance makes them both a curiosity and a prized treasure for houseplant enthusiasts. Yes, lithops can be a challenge to grow, but success is possible if they receive enough sun and are grown in very well-drained potting mix. You also have to follow a particular watering schedule for the greatest chance of success growing living stones. You’ll learn more about how to take care of these tiny treasures later in this article, but let’s start with a better description of this funky little plant and why every houseplant lover should learn how to grow lithops.
What is a lithops plant?
Lithops are succulents in the family Aizoaceae. These little charmers are in the genus Lithops, and they are native to southern Africa. They really do look like stones. Their natural habitat is arid, rocky areas, which is why they evolved such a clever camouflage to protect themselves from browsing herbivores.
Each lithops plant has a pair of leaves that look more like squishy rubber pads than leaves, with a fissure separating them. A new pair of leaves emerges from the fissure each season, often in spring when the old leaves split open, revealing the emergence of these new leaves. Once this happens, the old leaves shrivel and die. Lithops have a single long taproot with small root hairs protruding from it.
In the autumn, a single flower emerges from the middle fissure. The flowers are yellow or white and sometimes they have a sweet and pleasant fragrance. The flowers are daisy-like and about a half-inch across. They open in the afternoon and close late in the day.
All lithops are very small plants, only growing an inch or so above the soil’s surface. This makes them a great houseplant choice for a small apartment, a sunny windowsill, or a well-lit countertop or vanity.
Types of lithops
There are many different types of lithops, and in their native habitat, they can grow into large colonies. There are several dozen species with many subspecies and varieties as well. Not all types of living stones are available in the plant trade, but there is a broad diversity of colors and varieties on the market to those interested in growing living stones. It’s fun to collect plants of every color and grow them singly or together to form stunning color combinations.
Popular lithops species include lesliei, marmorata, hookeri, helmutii, bromfieldii, and terricolor, among many others.
The markings and leaf color of each species and variety depends on the environment it evolved in or on its breeding if it was a variety created through cross-pollination (more on this in a bit). Lithops come in a curious range of colors and patterns, from muted gray, green, yellow, and brown to pink, cream, and orange. Some species also have lines and/or dots, making them even more collectable.
Lithops dormancy periods
One of the most critical things to understand when it comes to caring for lithops is their growth cycle. In their native climate, lithops have two periods of dormancy. After the new leaves develop in the spring and the summer soil dries out, lithops cease growing and shift into a dormant state throughout the hottest part of the year. When growing lithops as houseplants, it’s important to understand that this dormancy is normal, and the plant should be allowed to dry out in the summer as it would in its native climate.
The second dormancy period occurs after the autumn flowering cycle is finished. During the winter months, the plants slow down again and stop growing. Watering should slow to a near stop during the winter months, too.
When to water living stones
Since lithops evolved in a dry, hot climate, and they have thick, fleshy, water-storing leaves, it stands to reason that they require only minimal irrigation. Here are a few points to remember when it comes to watering lithops:
- The plants should be kept almost completely dry during the winter.
- Only begin to consistently water them after they’ve split open and the new set of leaves has begun to develop in the spring. The plant can then be given a small amount of water every 10 to 14 days using a small watering can.
- Then, slow down the watering in the heat of the summer, during the plant’s second dormancy.
- Begin increasing the frequency of irrigation again in the autumn, when the plants come into flower.
- Their growth is largely focused on the autumn, and that’s when they require the most water.
In other words, don’t water during the hot summer or the cold winter.
How to take care of living stones
Beyond being mindful of their watering needs, caring for these tiny houseplants requires just a few other important tasks.
• Pot them in sandy, well-drained potting medium. A mix meant for cacti, with extra perlite or pumice tossed in, is the best soil for lithops. If the soil stays too wet, the plant will rot. Overwatering is often fatal.
• After the new leaves emerge, the old leaves shrivel and dry. They can be cut or otherwise removed from the plant using a needle-nose pruners if you desire. Otherwise, they’ll eventually just drop away on their own.
• Lithops require ample sunlight; 5 or 6 hours of direct sunlight a day is best. A south-facing window is ideal. Spin the pot a quarter turn every few days to keep the growth even.
• If your lithops plant collection is outdoors in the summer, put them in a sunny spot under the eaves of the house or under another cover to shield them from rainwater since they should be kept dry and dormant during the heat of summer. Only water lithops in the summer if the leaves show signs of puckering. Even then, only add a small amount of water (1 or 2 tablespoons).
• There is no need to fertilize lithops as they are accustomed to living in ‘lean’ soils.
You’ll seldom need to repot these little cuties. Since they are such small plants, you can typically keep your lithops in the same pot for many years. Only after dividing any pups will you need to repot (see the Propagating Lithops section below). If you don’t separate the plants and your colony grows large, eventually you will need to move the cluster of plants into a slightly larger pot. Lithops have long taproots, so select a pot that’s 4 or 4 inches deep. Nestle the plants into the soil so their upper edge is barely protruding from the soil surface. Topping the pot with colorful aquarium gravel or naturally colored gravel creates a decorative display.
Making more living stones to share with friends or expand your collection is an enjoyable project. There are two ways you can propagate this plant.
Growing lithops from collected seeds
Lithops flowers develop into a seed capsule if pollinators are present or if you’re willing to pollinate the plants by hand using a small paint brush. Be sure to move the pollen from one plant over to another for good cross-pollination. Lithops seed takes about 8 to 9 months to fully develop within the capsule. Collect the seed when the capsule is dry but before it splits open by picking it and cracking it open with a hard object (don’t worry, you won’t harm the seeds inside). Germinating lithops seeds is fairly straightforward, though living stones plants grown from seed aren’t mature enough to flower until they’re several years old.
To plant lithops seeds, use a cactus-specific potting mix. Cover the seeds very lightly with a layer of sand and keep them moist by misting often using a pump-style mister. The soil surface should not be allowed to dry out. Keep the pot covered with a piece of clear plastic wrap until the lithops seeds begin to germinate, which can take several months.
You’ll get some curious natural hybrids with unique color patterns, often different from their parents when growing lithops from seed. Divide and pot up the baby plants when they’re a few months old.
Growing living stones from plant division
As the plants age, they often develop young offsets (sometimes called ‘pups’). These young plants naturally form next to their parent plant, eventually forming a little colony of plants. It’s easier to grow lithops by dividing and separating these offsets, but it’s a little less fun than growing from seed because the pups are always exact clones of their parents. Growing from seed gives you lots of surprise variations.
To divide the pups from their parents, dig up the plants gently, being sure to lift the complete tap root, then use a razor blade, scalpel, or a clean sharp knife to sever the pup from its parent. Pot the pups in containers of their own and repot the parent plant into its original container (or a new one, if you choose).
Can they be grown outdoors?
Living stones can be grown indoors or out, but in regions where winter temperatures are below 40 or 50 degrees F, the plants must be moved indoors and grown as houseplants during the winter.
No matter where you grow them, collecting and caring for a collection of these wonderful plants is a worthwhile effort for all houseplant parents. Once you start growing these cuties, you’re sure to develop a hardcore case of lithops love!
For more on growing houseplants, check out the following articles:
Pilea peperomiodes care
Phalaenopsis orchid repotting steps
Houseplant fertilizer basics
Air plant care tips
The best plants for apartments