Lithops, often called “living stones,” are specialized succulent plants native to the arid regions of southern Africa. Their appearance mimics the pebbles and rocks of their natural habitat, which is why their care is uniquely challenging for indoor growers. They are adapted to extreme environmental conditions and seasonal moisture scarcity. Successfully cultivating these plants requires a deep understanding of their native climate and an intentional effort to replicate it indoors. Ignoring the cues of their annual growth phases or providing standard houseplant care will likely lead to their quick demise.
Essential Environmental Setup
Lithops require extremely bright light to survive and maintain their characteristic low-to-the-ground shape. They need at least four to six hours of direct sunlight daily, making a south or east-facing windowsill the best placement. Insufficient light causes the plant to stretch vertically, a process called etiolation. They should be protected from the harsh, intense midday sun during the hottest parts of summer to prevent scorching.
The soil mix is critical, as Lithops are highly susceptible to root rot. They demand an exceptionally fast-draining, gritty substrate with very little organic material. A suitable mix should contain at least 80% inorganic components, such as pumice, coarse sand, decomposed granite, or lava rock. This high-mineral composition ensures that water drains rapidly.
Deep pots are preferred to accommodate the plant’s long taproot. Unglazed terracotta pots are recommended because their porous material allows moisture to wick away and evaporate quickly. Good airflow helps the substrate dry out faster, which is useful when plants are kept indoors. To keep the plant compact, the top of the body should only be slightly above the soil surface, often surrounded by a top dressing of gravel.
Mastering the Annual Watering Cycle
The plant’s moisture needs are directly tied to its yearly growth phases. Overwatering is the primary cause of death for these plants, often resulting in rot or improper growth. The general rule is to observe the plant’s appearance for visual cues. If there is any doubt about watering, it is always safer to wait.
Phase 1: Splitting (Winter/Early Spring)
Splitting occurs during winter and early spring when a new pair of leaves grows inside the old pair. The new leaves draw all necessary moisture and nutrients directly from the old, outer leaves. It is necessary to withhold all water during this entire phase, generally from late autumn until the following spring. Watering while the plant is splitting prevents the old leaves from drying out, which can cause stretched, stacked leaves or rotting.
The old leaves will shrivel, flatten, and eventually dry into papery husks as the new body emerges through the central fissure. This shrinking is a normal part of the cycle, and the plant must fully absorb the old leaves before moisture is reintroduced. The dry leaf material helps keep the new leaves compact and close to the soil line.
Phase 2: Transition/New Growth (Late Spring/Summer)
Watering can be cautiously resumed once the old leaf husks are completely shriveled and dry, typically in late spring or early summer. This marks the start of the plant’s active growth period and the time for its first substantial drink. Watering should be deep, soaking the entire pot to encourage taproot growth, but the soil must be allowed to dry out completely within a few days.
Watering frequency is low, perhaps every two to three weeks, and should be based on the plant’s appearance. If the sides of the Lithops look slightly wrinkled or sunken, it indicates the plant is utilizing internal moisture stores and might benefit from a light watering. If the plant body is plump and rounded, it contains enough moisture and should not be watered.
Phase 3: Rest/Dormancy (Mid-Summer)
As temperatures rise significantly, typically in mid-summer, the plant enters a period of dormancy. Watering must be stopped completely during this time, even if the plant shows signs of wrinkling. Applying water during summer dormancy, especially combined with high temperatures, guarantees root rot.
Phase 4: Flowering (Autumn)
The plant naturally breaks dormancy as temperatures cool in early autumn, often resulting in a flower emerging from the central fissure. Light watering can be resumed to support the flowering process and help the plant store energy for winter. Watering remains infrequent, with a deep soak every few weeks, until the flower dies back. Once the plant stops flowering, water should be withheld entirely to initiate the winter rest period.
Troubleshooting and Recovery
Lithops may still exhibit signs of stress related to light or moisture imbalances. A common symptom is wrinkling, which is not always a sign of thirst. If the entire plant body appears soft, shriveled, or sunken, and the soil is dry, it likely needs a drink, provided it is the correct time of year for watering.
Conversely, an overly plump or mushy appearance signals overwatering, which can lead to incorrect splitting or developing rot. Rot symptoms include the plant becoming soft, discolored, and potentially emitting a foul odor. If rot has progressed to the taproot, the damage is frequently fatal. Immediate action, such as emergency repotting into dry, gritty soil, is often the only recourse.
Etiolation, caused by inadequate light, results in the plant stretching and becoming noticeably taller. While the stretched growth itself is irreversible, the solution is to immediately move the plant to a brighter location to prevent further stretching. New growth in the following season should be compact if light conditions are corrected. Common houseplant pests like mealybugs can attack Lithops, often hiding in the fissure between the leaves or on the roots. Mealybugs can be treated with a cotton swab dipped in rubbing alcohol applied directly to the insects.