Astrophytum is a cactus unlike any other, and one of the few that scientists have not tried to combine with other species in any classification revisions. The star cactus is a name that he received for the characteristic view from above, and which could be given to him just like that – for the spectacular appearance that always distinguishes him in the collection of exotic succulents and other houseplants. Of course, first of all, we are talking about flowering astrophytum. And in order for the star cactus to successfully grow and bloom, you need to know the character, habits and little secrets of this unpretentious, in fact, guest from the hot deserts of Mexico and Texas.
A characteristic feature of all plants of the Astrophytum species is the presence on the spherical “body” of felt bundles-speckles, the natural purpose of which is to collect moisture. Some species have spines, others do not have a (“naked” variety), others have an unusual curved shape. The star cactus grows very slowly, begins to bloom already in the second year of life and blooms with proper care until autumn, although the life expectancy of one flower is no more than a couple of days. After that, a seedpod is formed in its place, which, after opening, also becomes similar to a star. The seeds of astrophytum are black-brown, helmet-shaped, the only way the plant reproduces.
Types of astrophytums with photos
There are about a dozen are known natural species. In addition, all kinds of cultivars are popular among flower growers – varieties obtained artificially. They are obtained either by selection in one variety series or by crossing.
It belongs to the “naked” cacti. The globular body is slightly flattened from above, has about 8-10 cm at its widest point and 6-8 cm in height. The ribs are weakly expressed, the sinus buds are located on them. The flowers are yellow, silky, with an orange-red core. If the plant stands in the open sun, its stem gradually acquires a characteristic bronze tint, but in the spring it requires shading, otherwise, it can get sick. It is easily crossed with the speckled astrophytum. It gives good germination, for the first year they grow up to 4 cm, in the second year the color appears. Of all the varieties, astrophytum requires the mildest conditions of detention.
The most famous varieties are:
- Multipunctatum – has a more pronounced pubescence.
- Nudum is devoid of the characteristic speckle.
- Texas – with sharper ribs and smaller bright white speckles.
Another completely spineless variety. The stem is at first regular spherical in shape, with age it stretches in length. Adult specimens are 10-20 cm in diameter. The smallest speckles have a white-gray color, the ribs are usually 5 (for which the episcopal mitre was called), but there are also deviations in both directions (4-8). Tetrahedrons are rare, but look very interesting. Only small specimens bloom.
Spherical at first, over the years, begin to lengthen and acquire a cylindrical shape with a height of 20 cm and 10 cm in diameter. The ribs are tall, well-defined, usually 7-9, spines curved, 3-5 cm in length. Flowers of intense yellow color with a darker throat are formed in early June at the very top and exclusively in the daytime. It blooms all summer.
The most hardy species, the stem of which eventually stretches to 30-35 cm. Silver speckles are oriented in the form of stripes, the spines are straight, up to 7-9 cm, but there are subspecies with curved spines and devoid of speckle. The inflorescence are pale yellow, opening characteristically for this species in early summer.
Care at home
Like all succulents growing in difficult natural conditions, astrophytum is unpretentious, but caring for these plants has its own characteristics.
Despite the fact that in nature the star cactus grows under the scorching sun, at home, its requirements vary somewhat. Young specimens easily get sunburn in direct sunlight. They are especially susceptible to a star-shaped appearance. In addition, the change of seasons also plays a role – in the spring, the plant must get used to bright lighting. This does not mean that pots with astrophytum do not need to be placed on the southern windows, but in the hours of the scorching sun they still need to be shaded.
But high temperatures for this cactus are the norm of life. The optimal recommended temperature regime for room conditions is + 25-28C in the active vegetative season, from mid-spring to autumn. In winter, a period of rest is necessary, and preparation for it begins in September. Usually, everything happens naturally, but with the onset of winter, the pot must be removed from the sun and put in the coolest place in the apartment. The optimal thermometer reading at this time is + 12-15C.
Frequent watering in this case is not only not required, but can also cause significant harm to the plant until its death. Even in the summer heat, there is a need to moisten the ground only when the earthen lump dries up completely. Only lower watering is allowed, either in a pallet or briefly immersing the pot in a container with water. To do this, it is better to choose the morning hours of a sunny day. The daytime of a rainy day is not the same thing! In winter, watering should be gradually reduced and reduced to nothing, because mistakes in this regard are the cause of many troubles. Dry air is the best medium for growing astrophytum, humidifying the air for it is not required even in summer.
The plant can not only be sprayed, but also watered in such a way that water falls on its stem!
It is recommended to feed only in the warm season and no more than 1 time per month. For this, any complex designed for cacti is suitable, but you need to use it in half the dose from the recommended. In winter, fertilizers are not applied.
A ready-made soil for cacti is quite suitable, and given that this variety favorably treats calcareous soil, you can reasonably add a little powdered activated carbon and/or lime crumb to the pot. When self-preparing a soil mixture, it is recommended to use leafy earth, coarse sand (preferably river sand) and charcoal in the same proportions.
Astrophytum, to put it mildly, does not like transplants, so you need to do them only as necessary. The need, in this case, is the tightness of the dishes, but since this cactus grows very slowly, it does not occur often.
Do not take dishes under the astrophytum for growth! This can lead to souring of the soil.
Transplantation is carried out by transshipment without cleaning the root system from the ground. In the new pot, it is necessary to ensure high-quality drainage, including large drainage holes in the bottom.
An important feature of planting astrophytum is the need to provide a protective separating layer between the root neck and the soil. For this purpose, any material that does not absorb moisture is suitable. Reliably and, moreover, effectively perform this role, in small pebbles.
Do not bury the root neck of astrophytum when planting!
The peculiarity of the reproduction of this succulent is that the seed method is the only one for this. But the process itself is practically no different from planting seeds of other cactus species. Basic rules of seed reproduction:
- Pre-sowing preparation of seeds consists of short-term (no more than 5-10 minutes) soaking them in a very weak solution of potassium permanganate.
- After sowing, the container should be closed with a film, jar or something else transparent to create a small greenhouse effect.
- Ventilate daily.
- The temperature should be in the region of + 18-20C, i.e. lower than required for adult plants in the warm season.
- At the time of the rise of seeds, the soil requires periodic moistening, preventing the stagnation of water.
Seeds germinate quickly enough, in a few days, and have good germination. After that, watering is reduced and care is carried out for an adult plant, but it should be remembered that seedlings at this stage easily get sunburn.
Possible difficulties of home cultivation of astrophytum
First, the plant is attractive to some insect pests. These are mealybugs and root worms, as well as shield worms. The disadvantages of care can cause the following troubles.
- The lower part of the stem wrinkles, soft spots of rot appear on it. Most likely, there was excessive watering (especially important in winter) or the root neck is in contact with the ground.
- No growth. First of all, it should be understood that this culture by its nature gives a very slow increase. But if it is practically absent or clearly insufficient, the irrigation system should be revised. In summer, it may not be enough, and in winter – too much.
- Cork spots on the “body” of the cactus. There may be several reasons. The plant can be affected by pests, have physical damage or have been subjected to hypothermia. In addition, there may be a lack of moisture in the heat or watering with too hard lime water.
- Soft spots of dark color. This is stem rot, which affects mainly weak specimens. The sore spot must be carefully cut with a sharp knife, the cut can be treated with wood ash or crushed activated carbon. Treat the soil with a disinfectant solution of carbendazim and review the conditions of detention.
- The stem has an uncharacteristic shape, stretching too much upwards. In winter, the cause may be too high a temperature of maintenance, in summer – lack of lighting.