The Lithops or Cactus stone , are a genus of succulent or succulent plants, with more than 100 species. They belong to the Aizoaceae family, native to southern and southern Africa, especially Namibia, Botswana, etc.
The most common or vulgar names of Lithops are, Live Stones, Living Stones, Stone Cactus, Stone Plants or Blooming Stones.
The name of living stones or stone plant, derives from its name, “lithos” in Greek, which means, stone and “ops” which means, form or similar.
Given its mimicry with stones or pebbles that surround it in their environment, they are almost invisible, especially for their predators.
Of the more than 100 species that exist in Lithops, the best known and most popular are Lithops bella, Lithops lesliei, Lithops schwantesii, Lithops insularis, Lithops karasmontana, Lithops aucampiae.
Description of the Lithops or Cactus stone.
The Lithops, are small very fleshy plants, formed by 2 leaves united in their length and that present drawings in their surface.
The flowers emerge from between the two leaves and are large flowers, yellow or white, which will give the seeds.
As we have said, they consist of two leaves, of a height of about 5 cm. and an outer diameter of between 1 and 3 cm, according to varieties.
They do not usually have a size greater than 8 cm in width and about 20 cm in length, in the 10 years of average life they have.
They can be presented as isolated specimens or forming groups. They are slow growing.
The flowers are perfumed and have 2 to 4 cm in diameter. The fruit contains numerous seeds, which open at the time of the rains.
In the rounded area of ??the leaves, they have an area, more or less translucent, with a veined appearance. Over there the plant collects light, to develop the chlorophyll function.
At the end of winter, a couple of new leaves are born in the center and grow at the expense of the nutrients of the leaves of the previous season. Little by little they become stiff and die.
How to care for and cultivate the Lithops.
The growth of the Lithops or Cactus stone, lasts from July to November, that is, from summer to the fall.
In the spring, what is left of the old stem is a kind of paper, which envelops the new one. As soon as some moisture, dew or rain falls, the new stem emerges from the old.
The Lithops or Cactus stone, can live a long time, its longevity allows to have the plant in the same pot, for about 10 or 20 years.
These plants, being from very hot and dry regions, are excellent for indoor cultivation.
We must avoid being outside for two reasons, the first, because they can get wet from the rains and from the dew, which could cause great damage and even burst them, if they absorb too much water and the second, because the birds and insects could bite them .
Lack of light
If they lack light, the new leaves will grow more than normal upwards, thus weakening the plants. To avoid it or to solve it, it is necessary to locate them in an area where the sunlight gets them .
The lighting should not be direct sunlight , although they prefer very bright areas .
Its cultivation is relatively easy.
The pot should be a bit large, as they have a large pivot. Also, you can group several Lithops in a pot and cover the surface substrate with pebbles.
It would be necessary to put more drainage in the substrate, since the humidity would build up over time. The ideal minimum temperature would be between, about 5 ° to 10 ° C. and tolerates extremes up to 35-45 ° C.
How to water and fertilize Lithops or Cactus piedra.
When do you have to water?
Irrigation is the most important and complicated task at the same time that you have to do when you have plants. With lithops it is not easy to know when to irrigate, although we can do some things to avoid excessive watering:
- One of them is to weight the pot with your hand once it is watered, and again after a few days . The wet substrate weighs more than when it is dry, so we will only have to memorize the weight it has in each of the situations to know more or less when it’s time to irrigate.
- Another option is to introduce a humidity meter . Just enter it will indicate if it is wet or dry, but to be more reliable it is important to introduce it again in other areas (near the plant, away from it) because normally the substrate is usually more humid just around the plant that near from the edge of the pot. Control the humidity, so that it is always lower than 55% and thus avoid sudden decay.
What water to use?
The most suitable irrigation water is that of rain , but since we cannot always get it we can fill a bucket with water from the tap and let it rest one night. The next day we will water with the water from the upper half of the bucket.
Watering in winter
In winter the lithops are at rest. This means that their growth is practically nil, and their water needs decrease. Due to the weather conditions the substrate remains moist for longer, so we have to reduce the frequency of irrigation.
In general, we will water once every 15 or 20 days , always taking into account the humidity of the substrate and the weather forecasts.
Remember: irrigation in cold seasons, (latency period) is deadly.
Another method people us in the growing season of the Lithops or Cactus stone , it should be watered only when the leaves are slightly wrinkled and softened when pressed delicately.
In this way they will never rot. They should be watered in the evening, so that the substrate and the ambient temperature are lower, since the roots could be burned.
Never spray these plants directly, even on the hottest days.
Fertilizer is very important for them to grow healthy. For this reason, during the entire growing season (spring and summer) they must be paid with mineral fertilizers , whether formulated specifically for cactus and succulents, or with Earth Pod , pouring a small spoonful once every 15 days or once a month.
You can dilute a good liquid fertilizer (half of what is indicated)
They are plants that are very resistant to pests and diseases, being their enemies like excess irrigation and cold.
Lithops are plants very sensitive to cold, especially hail and snowfall. They can withstand weak and punctual frosts of up to -2ºC, but the substrate must be dry . In the case of living in an area where the winters are colder, it is convenient to place them inside a greenhouse, or indoors in a room where there is plenty of light, for example near a window and protected from drafts (both cold and warm).
What substrate does Lithops need?
The substrate that the Lithops need, must be almost completely mineral.
They do not tolerate a high concentration of organic matter in the substrate, because it retains moisture for a long time, which could lead to death, due to rot.
The usual is to use a mixture of coarse river sand, very fine gravel, leaf mulch and very little organic matter mixed with charcoal, <10%.
You can also use substrate such as akadama or pomice.
Pruning, Transplantation and Pollination of Lithops.
The Lithops or Cactus stone, are not pruned. Eliminating leaves that dry, to prevent them from becoming a vehicle for parasitic diseases.
Transplantation, usually the Lithops transplant, is done every 2-3 years and the optimal period will be when the old leaves have been completely wrinkled and the new leaves have left.
Pollination. The Lithops, usually bloom during the summer period, although it can also be in autumn.
The flowers last for about a week and if they will be pollinated (they are self-sterile plants, therefore better in large groups) the seeds mature in about four days.
You can pollinate the Lithops, with a soft brush of natural bristles that will first pass over the anthers of the flower of a plant and then over the stigma of another plant being careful not to wet the flowers so as not to harm the pollen.
After about seven months of pollination, the seeds will be ripe.
After a few days, if they have been properly pollinated, we will see the capsule that contains the seeds develop, which has to be left on the plant until it dries completely. View image
For this and after about seven months, the seeds will be ready for the rainy season. In the following spring, take the capsule of the plant and support it on a wet sheet of paper or by spraying it with water spray.
After a few hours, if the seeds are already mature, the capsule will open itself, releasing the seeds. If it did not open, repeat the operation a few days later.
Multiplication of Lithops or Cactus stone.
The multiplication of Lithops, is by seed.
The best period can be either spring or autumn, periods in which it is not too hot that could harm the young plants.
Use small pots, about 10 cm, and each can contain 20 to 80 seeds.
Use the same indicated substrate mixture, well sieved and tight to cover the surface with a thin layer of coarse sand.
Also, you can arrange the seeds of the Lithops, on the surface and then put on a thin layer of fine sand.
Then cover the pot with clear plastic film, without sealing it. This will allow a constant temperature and keep the substrate moist.
Spray the substrate, do not puddle it.
Place the pot in a bright area without direct sunlight. Control humidity.
A week later, the new plants should start to emerge. Remove the plastic film, keep the soil moist and with good ventilation.
One month later, the plants should be sufficiently developed.
At 3-4 months the Lithops should have leaves that are sufficiently fleshy and more similar to adult plants.
Apply then a little fertilizer, half or a quarter of the indicated, once a month.
It has been proven that seeds germinate in greater proportion if they wait a few months, between 4 and 6 months, after harvesting.
The seeds of the Lithops or Cactus piedra, can be conserved over 7 years, without losing their ability to germinate.
Pests and diseases of the Lithops.
This symptom is attributed to excessive waterings, in the periods when the plant is at rest.
Remedy, regulate well the risks.
Pillbugs, mites, thrips, Sciara fly, snails, leafhoppers or leafhoppers.
Snails and slugs are mollusks that love these plants. To prevent them from ending up with them, the quickest and most effective is to put a few grains of molluscicide in the pots
Mealybugs and mites:
Leafhoppers or leafhoppers: