Lithops, often called “living stones,” are unique succulents that have evolved to blend seamlessly with their rocky, arid environments. Their specialized watering needs are distinct and often counter-intuitive compared to most other plants. Proper watering is essential for their survival and ability to thrive.
Understanding Lithops’ Unique Water Needs
Lithops originate from arid regions of southern Africa, where rainfall is scarce. They store water in their thick, fleshy leaves, which are essentially inverted cones with only their tops exposed above the soil line. This structure, combined with their stone-like appearance, allows them to camouflage from herbivores and minimize water loss through evaporation.
Their bodies are designed for water conservation, enabling them to endure months without rain by shrinking below the soil surface during dry spells. Lithops also possess specialized taproots that efficiently absorb moisture when it becomes available. Understanding these natural adaptations and their dormancy cycles is fundamental, as these cycles dictate their watering needs, a stark contrast to the consistent watering needs of typical houseplants.
The Seasonal Watering Cycle for Lithops
The watering schedule for Lithops is tied to their annual growth cycle, which often reverses typical Northern Hemisphere seasons. In autumn and early winter, as temperatures cool, Lithops emerge from summer dormancy and enter a period of active growth. This is when watering can resume, providing thorough drenching to encourage development and prepare for flowering. Signs of renewed activity include the fissure between the leaves separating, often preceding flower bud emergence.
During late winter and early spring, Lithops enter their “splitting” phase, where a new pair of leaves develops from within the old pair. Completely cease watering during this period, as the new leaves absorb moisture and nutrients from the old, outer leaves. Introducing water prematurely can disrupt this process, leading to elongated or stacked growth, or even cause the new leaves to rot before they fully emerge. The old leaves will gradually shrivel and become papery husks as their water is transferred.
By late spring to early summer, after the old leaves have withered, the new plant body will be visible and plump. A light watering might be given if the plant shows signs of thirst, such as slight wrinkling or softening, but this is usually a brief window before summer dormancy. Some varieties may flower during this time, and less water is needed during blooming. As summer progresses, Lithops enter their natural dormant period to protect themselves from heat and drought.
Complete cessation of watering is important throughout the hot summer months, as any moisture can lead to fatal rot. While some shriveling is normal during dormancy, a severely shriveled plant might benefit from a very light misting, but deep watering must be avoided. This seasonal guide is general; variations can occur based on local climate, species, and individual plant behavior.
Best Practices for Watering Lithops
Determining when to water Lithops relies on observing the plant itself, rather than a fixed schedule or checking soil dryness. A healthy Lithops will feel firm and appear plump; signs of thirst manifest as the sides of the plant flattening or developing noticeable wrinkles. It is important to distinguish these signs from the natural shriveling of old leaves during the splitting phase or the slight shriveling that occurs during summer dormancy, which do not necessarily indicate a need for water.
When watering, a thorough drenching method is recommended. This involves saturating the potting medium, allowing water to drain freely from the bottom of the pot. This encourages the development of a deep, healthy root system as the roots seek out moisture. After watering, it is important to allow the soil to dry out completely before considering the next watering, which can take a week or two depending on conditions and pot size.
Good airflow around Lithops is also important, as stagnant, humid conditions can contribute to problems even with proper watering. Ensuring thorough saturation and subsequent drying is key. The goal is to mimic their natural infrequent but substantial rain events.
Common Watering Problems and Solutions
Overwatering is the most frequent and often fatal mistake when caring for Lithops. Symptoms include a mushy texture, bursting leaves, or rot at the plant’s base. If overwatering is suspected, cease all watering and allow the soil to dry completely. If rot is not severe, the plant might recover; otherwise, repotting into fresh, dry substrate after removing any rotted sections may be necessary.
Watering Lithops during their splitting phase is another common issue. This occurs as new leaves develop inside the old ones, absorbing moisture from the older pair. Watering at this time can cause the old leaves to retain water, preventing proper absorption and potentially leading to elongated, “stacked” growth or even rotting the new leaves. Stop watering and allow the natural absorption process to complete.
Underwatering is less common for Lithops due to their drought tolerance, but it can occur. Symptoms include excessive, persistent shriveling and wrinkling that does not plump up after a long dry spell, indicating the plant’s water reserves are low. To address this, rehydration is needed; provide a thorough soak, but monitor the plant closely to ensure it absorbs water and plumps up without becoming waterlogged. Lithops are resilient to drought, making it safer to err on the side of underwatering than overwatering.