Cereus is a truly giant cactus. Under natural conditions, some of its species are able to grow up to 20 meters in height. The average plant size is about 10 m. Cereus can achieve this growth due to a very long life. The name of the species in Latin means "candle".
You can meet such unusual plants in South America, as well as in some regions of India. You can admire a life-size cactus only in botanical gardens or individual shops. Miniature varieties of this barbed "candle" are more suitable for home breeding.
Flowering cereus
Naturally growing cacti begin to bloom in late spring - from May to June. Most of the varieties of cereus open their flowers only at night. They are located on the sides of the stems, and not on their tops. Almost all Cereus flowers are large and white. The yellow center serves as a bright spot. A pleasant, but sometimes very rich aroma is added to the external beauty. In some species, the smell of flowers resembles vanilla.
Cereus flowers are kept open for only 24 hours. In nature, their short flowering period is compensated by the fact that several buds on one plant can bloom simultaneously or one after another. But it is almost impossible to achieve such abundant flowering at home. Sometimes, homemade cereus refuse to bloom at all. This is usually caused by improper containment conditions. The plant requires long daylight hours, so in indoor conditions it often suffers from a lack of sunlight. Because of this, flowers on it may appear very rarely or not at all.
Other reasons for the lack of flowers include improper care during the dormant period, watering errors, lack of ventilation, and the age of the specimen is too small. If all these conditions are met, the cactus should bloom at its usual time - by the beginning of summer. But some species begin to form buds closer to autumn.
Cereus care at home
In general, the Cereus cactus is not too capricious and grows well at home. Due to the special endurance of this plant, it is used as a rootstock for more demanding and whimsical cactus plants. Such vaccinations have contributed to the production of new varieties that combine beauty with greater durability.
Location and lighting
Cereus is photophilous, a sufficient level of lighting is necessary for him both in summer and during rest. A south or southeast window is suitable for a flower. But hitting straight lines with the best during strong solar activity often leaves burns on the surface of the stems.This can be avoided by gradually adapting the cactus to bright direct light.
Temperature
In spring and summer, Cereus prefers warmth, but it is not afraid of extreme heat or temperature changes. With the onset of suitable weather, it is recommended to transfer it to the air, placing it in a loggia or on a veranda until the beginning of autumn. Cereus rests in winter. During this period, it must be kept in a room where the temperature does not exceed +12 degrees.
Watering schedule
For cereus, only soft water is suitable. It should be moderately warm, and by no means icy. Waterlogging leads to plant diseases. In addition, you should try not to pour it directly onto the stem, choosing places closer to the edge of the pot. You can also water the cactus through the sump, draining excess water in a timely manner.
In spring and summer, the amount of watering should be moderate, in winter - very small. The lower the temperature in the room, the less often the plant should be watered.
Air humidity
Cereus easily tolerates drought and dry air is not afraid of him. But in spring and summer, you can slightly humidify the air around the cactus, periodically spraying it with lukewarm water.
Top dressing
Cereus grows fast enough and needs regular fertilization. Top dressing is carried out only during the active development of the plant: from about April to July. It is best to dilute the required substances in water for irrigation. For top dressing, universal fertilizers for cacti are suitable, which include potassium, which strengthens their stems and promotes the setting of buds. The phosphorus in these formulations aids in root growth and flowering. Calcium is necessary for the strength of the needles, in addition, without it, the stems will become more brittle.
If the cactus has been transplanted into fresh soil, it should not be fed for a while. Fertilizer is taken after a few weeks, when the nutrients present in the soil begin to be depleted.
Soil selection
Cereus will suit neutral or acidic soil. You cannot plant a plant in an alkaline environment. Harmful to cactus and soil rich in humus.
To provide additional drainage, small brick debris and river sand are added to the soil for planting.
Transfer
The plant is transplanted every couple of years if the old pot becomes cramped for him. The new container must be both high and wide. The optimal time for the procedure is mid-spring, when the cereus begins to come out of hibernation, but you can do transplants until the end of the active phase. If the cactus is not cramped in its capacity, but it grows too slowly, you can try not to change the pot, but replace the soil in it.
When removing a cactus from an old pot, it is worth examining its roots and removing dry or rotten ones. It is important to stand for several days without watering before transplanting. The drier the land, the easier the process will go. In order not to prick on the thorns on the stem, you can wrap the cereus with several layers of paper or use special transplanting tools.
Dormant period
Cereus should spend winter in a very bright and slightly cool place. Having put the pot in the chosen place, it is better not to disturb the plant and not turn the container. Top dressing during this period is not applied, and watering is reduced to a minimum.
Reproduction of cereus
In the natural environment, cereus reproduces with the help of seeds. Sometimes the broken off parts of its stem take root and take root. This allows you to get new plants by cuttings: in potting conditions, rocky species of this cactus reproduce only in this way.
Seeds should be planted starting in mid-spring. The soil for planting should not be too damp. Until shoots appear, the container with seeds can be covered with a film and placed in a shady corner, periodically removing the film for airing. As soon as the sprouts appear, it is transferred to a bright place where direct sunlight does not fall. Supplementary lamps can be used. The optimum temperature for keeping small cacti is about +25.
A month later, the first spines begin to appear on the shoots.During this period, you need to divide the seedlings. The final transplant into individual containers can be done a little later.
To propagate the cereus by cuttings, shoots are cut from the mother plant. It is best to cut during the growth of the cactus, from late spring to mid-summer. The cuttings are dried in the air for several days. After that, they are planted in a low pot with moist soil. As a rule, the cutting has time to set in within a month. After rooting, you can transplant the new cactus into a permanent container. Caring for such a graft is no different from caring for a mother's Cereus.
Diseases and pests
The main risk is fungal diseases. Due to overflow, soft brownish rot spots are formed on the shoots. Most often they look depressed. A small rotten area can be carefully cut out with a sharp knife. Then the place is treated with a disinfectant: you can use alcohol. Further care will consist in leveling the irrigation regime. The first time after the procedure for removing the affected area, the cereus is watered much less often. If the roots have begun to rot, the missing ones should be removed. In advanced cases, you can try to save the upper part of the stem by rooting it like a cutting.
Many pests can settle on a cactus. Reddish dots on the surface of the stem and a coating of cobwebs indicate the presence of spider mites. If you do not get rid of them, the cactus will be covered with dry yellow spots. If the spots on the stem are whitish and covered with fluff, then the culprit is the mealybug. Small round or oval bugs, noticeable without effort, are scale insects or false scales that drink the sap of the plant. A suitable insecticide will help get rid of any pests. But in order to prevent their appearance, you can periodically process the plant as a preventive measure.
A careful examination of the cereus will also be important. It is worth looking closely at all the folds and the lower region of the plant stem. This will help to timely notice the attack of insects or mistakes in the care of the cactus.
Possible difficulties
Cereus is able to add trouble to the grower with its rapid growth. For a small apartment, this cactus may be too large.
Avoid keeping a blooming adult plant in the bedroom: the rich scent of flowers can cause sleep problems.
The main types of cereus with a photo
Cereus peruvian (Cereus peruvianus)
The stem of the peruvianus cactus has a cylindrical shape with distinct ribs. As a potted culture, the Peruvian species can reach half a meter or even a meter in height. It reveals its fragrant snow-white flowers only at night. The fruit is edible, outwardly it resembles a red-orange berry.
The rocky cereus has a bizarre variety called the monstrous. Its stems are bent so much that they form amazing outlines. Florists appreciate this variety very much for its external originality.
Cereus repandus
The repandus cactus is not always considered a separate species. Most often it is considered a variation of the rocky cereus.
Cereus jamacaru
The jamacaru species has slender stems. They are also cylindrical in shape. The ribs of the cactus are covered with small light spines. You can also see Yamakaru flowers only at night. They have impressive dimensions: up to 20 cm.
Cereus giant desert giant (Cereus giganteus)
The largest species can be seen in the US states of California and Texas. It is also found in Arizona: moreover, the flower of the plant is considered its symbol. Due to its huge size (25 m in height), this species is included in the Guinness Book of Records.
A distinctive feature of the giant cereus is its growth rate. Until the 30th anniversary, it develops very slowly, but then it begins to increase the pace. In a cactus, the shape of the trunk changes, from which a whole series of lateral stems begins to emerge.
The gigantic size does not prevent this cactus from blooming and bearing fruit. Its red berries are eaten and very tasty.
Cereus validus
Young stems of this cactus are bluish in color and can branch. Usually there are up to 8 ribs on each stem. Validus flowers are also white in color.
Cereus uruguayanus (Cereus uruguayanus)
This species has bluish-green stems. They have over 5 ribs with sharp and rather long (up to 2 cm) spines.
Cereus azure (Cereus azureus)
The name of the variety is due to the smoky blue color of the stems. Many shoots are formed on them. At the same time, the ribs on them are not clearly expressed. The flowers are white and have a strong aroma.
