What are Lithops or living stones?
The Lithops, known as "living stones," are succulents native to arid regions of Africa, primarily South Africa and Namibia. They are distinguished by their camouflage appearance, which allows them to blend in with the stones in their surroundings to avoid being eaten by animals. These plants develop a single head or several, formed by two fused fleshy leaves, with a central fissure where the flower appears. Their life cycle and appearance have evolved to survive in extreme conditions. resisting long periods of drought and variable temperatures.
Name Lithops derives from Greek lithos (stone) and opsis (appearance), referring to their mimetic characteristics. They are small, long-lived, and perfect for succulent collections due to their wide range of patterns, shapes, and colors.
History, origin and taxonomy
The botanical discovery of Lithops It is attributed to William John Burchell, who first described these plants in South Africa. Since then, various expeditions have expanded knowledge of their distribution thanks to discoveries in Namibia, Botswana, Angola, Mozambique, and Zimbabwe.
Botanically, Lithops belongs to the family Aizoaceae, which includes other succulent plants adapted to arid lands. Although there are similar genera such as Conophytum, Pleiospilos o Fenestrary, only Lithops exhibits this unique combination of mimicry and life cycle.
There are more than 35 recognized species and a multitude of varieties., differentiated by patterns, markings and colors that have evolved according to the habitat of each species to ensure their camouflage.
Morphological characteristics and life cycle
A typical Lithops presents two leaves fused together forming a flattened, oval structure, in shades ranging from grays, browns, and greens to pinks, often decorated with patterns of lines, spots, or translucent windows. These windows allow light to pass through to photosynthetic tissues below the surface, a key adaptation for survival in areas where sunlight is intense but scarce for part of the year.
Its annual cycle It is divided into four phases:
- Winter break: The plant stops its visible growth and the old leaves begin to wither from the base.
- Moult (spring): New leaves emerge within the head, absorbing nutrients and water from the old leaves.
- Summer break: In the middle of summer, growth and physiological activity stop to withstand the high temperatures.
- Flowering (autumn): A central flower appears, usually yellow or white, which can last for several days.
This closed and repetitive cycle is essential for success in home cultivation.
The ideal substrate for Lithops: composition and preparation
The key to growing Lithops lies in the substrateThis should be highly mineralized, with excellent drainage and low organic matter. An organic substrate tends to retain too much moisture and can promote fungus or rot. Therefore, it is ideal to use mixtures that include pebbles, granite gravel 1 to 4 mm, coarse river sand y pumice, avoiding calcareous materials and commercial substrates for cacti that usually exceed in organic matter.
Recommended mixing method:
- 4 parts aquarium sand (half fine, half medium)
- 3 parts crushed pumice stone
- 1 part universal black soil (optional, only if it is of good quality and low in nutrients)
The maximum particle size should be 3 mm and, if possible, sift the mixture to separate larger particles. Before use, the substrate must be sterilized in the oven or microwave to eliminate fungal spores. A base of gravel or pebbles about 12 mm thick at the bottom of the pot promotes drainage.
It is not advisable to use peat or rich substrates that promote the development of fungi or pests.
Choosing a pot: dimensions, materials and drainage
The choice of pot is essential for root development. of Lithops. Although they are small plants, they develop long and deep roots. It is recommended to use pots between 7 and 10 cm deep At the very least, the material can be clay (recommended for its rapid evaporation and aeration) or opaque plastic (never transparent to prevent algae), always with drainage holes. In large pots, 3 or 4 holes covered with a pebble are sufficient.
Square pots optimize space for collections and allow you to differentiate varieties or species. If you grow several plants in a single pot, leave at least two centimeters of separation between specimens.
Basic care for adult Lithops
Light and location
Light is essential for proper growth and flowering.It's recommended to place Lithops in a location with at least 4 to 5 hours of direct sunlight in the morning and partial shade in the afternoon. If grown indoors, the location should be an east- or south-facing window. Too much sun can cause sunburn, while too little light induces etiolation (slow, stunted growth).
Ventilation
A well-ventilated environment is essential to reduce the risk of rot. Lithops are not strictly houseplants, as they require constant ventilation and low night temperatures to simulate their habitat. Keep away from artificial heat sources such as radiators or heaters.
Temperature
The temperature difference between day and night It promotes growth and flowering. Lithops tolerate low temperatures, even near zero for short periods, but they cannot tolerate prolonged frost. The recommended minimum temperature is around 10°C. Shade cloth can be useful in hot summers to protect from intense radiation.
Irrigation: how, when and how often
El biggest challenge and cause of death in Lithops It is excessive irrigation. They follow a natural cycle with long periods of drought:
- Do not water during the rest period (winter). Allow the plant to absorb water from the old leaves.
- Resume watering when the shedding is complete and new leaves appear, using moderate water and only when the plant demands it (if it becomes excessively wrinkled).
- During the vegetative phase, water only every 3 to 4 weeks or less, always waiting for the substrate to be completely dry between waterings.
- In humid places, they can go up to 6 months without watering.
Using rainwater is ideal, as hard or calcareous water can negatively affect the plant's health. Use a fine-necked watering can or sprayer to prevent waterlogging in the central fissure of the plant.
Fertilization and fertilization
Lithops hardly require fertilization.Their natural habitat is nutrient-poor, making regular fertilizer unnecessary. Only after two or three years of cultivation in the same substrate can a cactus fertilizer low in nitrogen and high in potassium be added, diluted at half the recommended dose and only during the active growth stage (spring/fall).
Transplant: when and how to do it
Lithops are best repotted when the plant enters dormancy or has just finished shedding, always with the substrate dry. It is recommended to repot every two years or only if the plant requires it. After repotting, leave without watering for at least 5 days so that the roots can heal and place them in semi-shade gradually before exposing them to direct sunlight.
Lithops Reproduction: Seed and Advanced Methods
Reproduction from seed is the most effective and rewarding method to obtain new Lithops, allowing for an expanded variety collection and experimentation with different patterns and colors. Seed viability is high, and many species maintain their germination capacity for more than a decade if stored in a dry, dark place.
Seedbed preparation and sowing
- The best time to sow is in late spring or early summer in temperate regions, to allow the seedlings to reach a sufficient size by winter.
- Use deep, square pots (7-10 cm), filled with sterilized mineral substrate (see substrate section).
- On the surface, place a layer of fine sand of about 3 mm and scatter the seeds without burying them. Use seeds aged at least one year, as they germinate more regularly.
- Spray the surface with rainwater and cover the pot with perforated clear plastic to maintain humidity, allowing air circulation.
- Place the seedbed in a bright location but not in direct sunlight. The ideal germination temperature is between 20°C and 28°C.
- Water by immersion, partially submerging the pot in water (with fungicide at the beginning), avoiding puddles.
Seedling care
Germination usually occurs between 4 and 8 days after sowing. Once most of the seeds have sprouted, Remove the plastic and water only by spraying, allowing the surface layer of the substrate to dry between waterings but keeping it slightly moist at a depth of about 6 mm. Seedlings require more water than adult plants, so they should be watered every three or four weeks until they reach about 18 months of age. It is very important do not drastically change the light or humidity conditions, avoiding direct sunlight and sudden changes in environment.
Advantages and considerations of growing from seed
- Sexual reproduction allows us to obtain plants of great genetic diversity.
- The germination rate is high, but it is common for some seeds to take months or years to germinate.
- Seedlings develop deep roots and can remain in the same pot for 18 months or more before transplanting.
- The simplest species for beginners are: Lithops aucampiae, bromfieldii, hallii, hookeri, karasmontana, lesliei, olivacea, pseudotruncatella, salicola y schwantesii.
Common problems and mistakes in Lithops cultivation
Long-term success lies in avoiding common mistakes:
- Excess watering: Causes swelling, cracking, rotting and death.
- Lack of light: Lithops stretch (etiolation), discolor, and may die without flowering.
- Incorrect transplants: Transplants at the wrong time or with wet roots can cause rot.
- Pests: Mealybugs are the most common pests, followed by rootworms. It's important to inspect the roots and apply systemic insecticides when necessary.
- Fungi and algae: Consequence of constant humidity; prevent by sterilizing the substrate and regulating ventilation.
Proper care, plant observation and patience, are essential to avoid the premature death of Lithops, which can live for decades.
Recommended varieties and species
There are more than 35 species and more than 145 varietiesThey vary in color, markings, shapes, and sizes, making them highly collectible specimens. Some of the most popular:
- Lithops aucampiae
- Lithops bromfieldii
- Lithops karasmontana
- Lithops lesliei
- Lithops optic
- Lithops pseudotruncatella.
- Lithops salicola
- Lithops schwantesii
- Lithops hookeri
- Lithops dorotheae
- Lithops verruculosa
- Lithops fulviceps
- Lithops ruschiorum
- Lithops localis
The flowering pattern It varies between species, but most flower from the third year of life, provided they have received sufficient light and are cared for correctly.
Tips for keeping Lithops in optimal condition
- Clay pots with drainage they promote aeration and the elimination of excess moisture.
- Bright location but without direct sunlight during the central hours of the day.
- Water only when the old leaves are completely dry and the new ones have emerged.
- Do not over-fertilize or transplant outside the recommended growth phases.
- Avoid sudden changes in environment, temperature or light.
Frequently asked questions about Lithops or living stones
- How long do Lithops live? They can live over 40-50 years in suitable pots and with optimal care.
- Why is my Lithops cracking or swelling? Generally, this is due to overwatering or a lack of a dry period. Adjusting the frequency and amount of water is essential.
- How do I prevent my Lithops from etiolating? Provide as much light as possible without constant direct sunlight; lack of light is the main cause of etiolation.
- When to transplant Lithops? At the beginning of the growth period, with dry substrate and letting the plant rest after transplanting.
- Can they thrive indoors? Yes, as long as they receive direct sunlight at least mid-morning and good ventilation.
Learn to grow Lithops or living stones Requires patience and attention to detail, replicating the conditions of their natural environment. With the right mineral substrate, a deep, well-draining pot, strict watering control, and bright but not direct exposure during peak sunlight hours, these little desert treasures can thrive for decades, brightening any succulent collection with their unparalleled form and blooms.